Fix whitespace in CMakeLists.txt

- all spaces no tabs
- indent with 4 spaces everywhere
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 03969f4..a89a9bc 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -4,26 +4,26 @@
 string(REGEX MATCH "Clang" CMAKE_COMPILER_IS_CLANG "${CMAKE_C_COMPILER_ID}")
 
 if(CMAKE_COMPILER_IS_GNUCC)
-  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -W -Wdeclaration-after-statement -Wwrite-strings -Wlogical-op")
-  set(CMAKE_C_FLAGS_RELEASE     "-O2")
-  set(CMAKE_C_FLAGS_DEBUG       "-O0 -g3")
-  set(CMAKE_C_FLAGS_COVERAGE    "-O0 -g3 --coverage")
-  set(CMAKE_C_FLAGS_ASAN        "-Werror -fsanitize=address -fno-common -O3")
-  set(CMAKE_C_FLAGS_ASANDBG     "-Werror -fsanitize=address -fno-common -O1 -g3 -fno-omit-frame-pointer -fno-optimize-sibling-calls ")
-  set(CMAKE_C_FLAGS_CHECK       "-Werror -Os")
-  set(CMAKE_C_FLAGS_CHECKFULL   "${CMAKE_C_FLAGS_CHECK} -Wcast-qual")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -W -Wdeclaration-after-statement -Wwrite-strings -Wlogical-op")
+    set(CMAKE_C_FLAGS_RELEASE     "-O2")
+    set(CMAKE_C_FLAGS_DEBUG       "-O0 -g3")
+    set(CMAKE_C_FLAGS_COVERAGE    "-O0 -g3 --coverage")
+    set(CMAKE_C_FLAGS_ASAN        "-Werror -fsanitize=address -fno-common -O3")
+    set(CMAKE_C_FLAGS_ASANDBG     "-Werror -fsanitize=address -fno-common -O1 -g3 -fno-omit-frame-pointer -fno-optimize-sibling-calls ")
+    set(CMAKE_C_FLAGS_CHECK       "-Werror -Os")
+    set(CMAKE_C_FLAGS_CHECKFULL   "${CMAKE_C_FLAGS_CHECK} -Wcast-qual")
 endif(CMAKE_COMPILER_IS_GNUCC)
 
 if(CMAKE_COMPILER_IS_CLANG)
-  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -W -Wdeclaration-after-statement -Wwrite-strings -Wpointer-arith")
-  set(CMAKE_C_FLAGS_RELEASE     "-O2")
-  set(CMAKE_C_FLAGS_DEBUG       "-O0 -g3")
-  set(CMAKE_C_FLAGS_COVERAGE    "-O0 -g3 --coverage")
-  set(CMAKE_C_FLAGS_ASAN        "-Werror -fsanitize=address -fno-common -fsanitize=undefined -fno-sanitize-recover -O3")
-  set(CMAKE_C_FLAGS_ASANDBG     "-Werror -fsanitize=address -fno-common -fsanitize=undefined -fno-sanitize-recover -O1 -g3 -fno-omit-frame-pointer -fno-optimize-sibling-calls ")
-  set(CMAKE_C_FLAGS_MEMSAN      "-Werror -fsanitize=memory -O3")
-  set(CMAKE_C_FLAGS_MEMSANDBG   "-Werror -fsanitize=memory -O1 -g3 -fno-omit-frame-pointer -fno-optimize-sibling-calls -fsanitize-memory-track-origins=2")
-  set(CMAKE_C_FLAGS_CHECK       "-Werror -Os")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -W -Wdeclaration-after-statement -Wwrite-strings -Wpointer-arith")
+    set(CMAKE_C_FLAGS_RELEASE     "-O2")
+    set(CMAKE_C_FLAGS_DEBUG       "-O0 -g3")
+    set(CMAKE_C_FLAGS_COVERAGE    "-O0 -g3 --coverage")
+    set(CMAKE_C_FLAGS_ASAN        "-Werror -fsanitize=address -fno-common -fsanitize=undefined -fno-sanitize-recover -O3")
+    set(CMAKE_C_FLAGS_ASANDBG     "-Werror -fsanitize=address -fno-common -fsanitize=undefined -fno-sanitize-recover -O1 -g3 -fno-omit-frame-pointer -fno-optimize-sibling-calls ")
+    set(CMAKE_C_FLAGS_MEMSAN      "-Werror -fsanitize=memory -O3")
+    set(CMAKE_C_FLAGS_MEMSANDBG   "-Werror -fsanitize=memory -O1 -g3 -fno-omit-frame-pointer -fno-optimize-sibling-calls -fsanitize-memory-track-origins=2")
+    set(CMAKE_C_FLAGS_CHECK       "-Werror -Os")
 endif(CMAKE_COMPILER_IS_CLANG)
 
 set(CMAKE_BUILD_TYPE ${CMAKE_BUILD_TYPE}
@@ -31,9 +31,9 @@
     FORCE)
 
 if(CMAKE_BUILD_TYPE STREQUAL "Coverage")
-  if(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_CLANG)
-    set(CMAKE_SHARED_LINKER_FLAGS "--coverage")
-  endif(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_CLANG)
+    if(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_CLANG)
+        set(CMAKE_SHARED_LINKER_FLAGS "--coverage")
+    endif(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_CLANG)
 endif(CMAKE_BUILD_TYPE STREQUAL "Coverage")
 
 option(USE_PKCS11_HELPER_LIBRARY "Build mbed TLS with the pkcs11-helper library." OFF)
@@ -43,65 +43,65 @@
 option(ENABLE_TESTING "Build mbed TLS tests." ON)
 
 if(ENABLE_TESTING)
-  enable_testing()
+    enable_testing()
 endif()
 
 if(LIB_INSTALL_DIR)
 else()
-set(LIB_INSTALL_DIR lib)
+    set(LIB_INSTALL_DIR lib)
 endif()
 
 include_directories(include/)
 
 if(ENABLE_ZLIB_SUPPORT)
-  find_package(ZLIB)
+    find_package(ZLIB)
 
-  if(ZLIB_FOUND)
-    include_directories(${ZLIB_INCLUDE_DIR})
-  endif(ZLIB_FOUND)
+    if(ZLIB_FOUND)
+        include_directories(${ZLIB_INCLUDE_DIR})
+    endif(ZLIB_FOUND)
 endif(ENABLE_ZLIB_SUPPORT)
 
 add_subdirectory(library)
 add_subdirectory(include)
 
 if(ENABLE_TESTING)
-  if(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_CLANG)
-    add_subdirectory(tests)
-  endif(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_CLANG)
+    if(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_CLANG)
+        add_subdirectory(tests)
+    endif(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_CLANG)
 endif()
 
 if(ENABLE_PROGRAMS)
-  add_subdirectory(programs)
+    add_subdirectory(programs)
 endif()
 
 ADD_CUSTOM_TARGET(apidoc
-                  COMMAND doxygen doxygen/mbedtls.doxyfile
-                  WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
+    COMMAND doxygen doxygen/mbedtls.doxyfile
+    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
 
 if(ENABLE_TESTING)
-  ADD_CUSTOM_TARGET(covtest
-    COMMAND make test
-    COMMAND programs/test/selftest
-    COMMAND cd tests && ./compat.sh
-    COMMAND cd tests && ./ssl-opt.sh
+    ADD_CUSTOM_TARGET(covtest
+        COMMAND make test
+        COMMAND programs/test/selftest
+        COMMAND cd tests && ./compat.sh
+        COMMAND cd tests && ./ssl-opt.sh
     )
 
-  ADD_CUSTOM_TARGET(lcov
-    COMMAND rm -rf Coverage
-    COMMAND lcov --capture --initial --directory library/CMakeFiles/mbedtls.dir -o files.info
-    COMMAND lcov --capture --directory library/CMakeFiles/mbedtls.dir -o tests.info
-    COMMAND lcov --add-tracefile files.info --add-tracefile tests.info -o all.info
-    COMMAND lcov --remove all.info -o final.info '*.h'
-    COMMAND gendesc tests/Descriptions.txt -o descriptions
-    COMMAND genhtml --title "mbed TLS" --description-file descriptions --keep-descriptions --legend --no-branch-coverage -o Coverage final.info
-    COMMAND rm -f files.info tests.info all.info final.info descriptions
+    ADD_CUSTOM_TARGET(lcov
+        COMMAND rm -rf Coverage
+        COMMAND lcov --capture --initial --directory library/CMakeFiles/mbedtls.dir -o files.info
+        COMMAND lcov --capture --directory library/CMakeFiles/mbedtls.dir -o tests.info
+        COMMAND lcov --add-tracefile files.info --add-tracefile tests.info -o all.info
+        COMMAND lcov --remove all.info -o final.info '*.h'
+        COMMAND gendesc tests/Descriptions.txt -o descriptions
+        COMMAND genhtml --title "mbed TLS" --description-file descriptions --keep-descriptions --legend --no-branch-coverage -o Coverage final.info
+        COMMAND rm -f files.info tests.info all.info final.info descriptions
     )
 
-  ADD_CUSTOM_TARGET(memcheck
-    COMMAND sed -i.bak s+/usr/bin/valgrind+`which valgrind`+ DartConfiguration.tcl
-    COMMAND ctest -O memcheck.log -D ExperimentalMemCheck
-    COMMAND tail -n1 memcheck.log | grep 'Memory checking results:' > /dev/null
-    COMMAND rm -f memcheck.log
-    COMMAND mv DartConfiguration.tcl.bak DartConfiguration.tcl
+    ADD_CUSTOM_TARGET(memcheck
+        COMMAND sed -i.bak s+/usr/bin/valgrind+`which valgrind`+ DartConfiguration.tcl
+        COMMAND ctest -O memcheck.log -D ExperimentalMemCheck
+        COMMAND tail -n1 memcheck.log | grep 'Memory checking results:' > /dev/null
+        COMMAND rm -f memcheck.log
+        COMMAND mv DartConfiguration.tcl.bak DartConfiguration.tcl
     )
 endif()