Fix whitespace in CMakeLists.txt

- all spaces no tabs
- indent with 4 spaces everywhere
diff --git a/programs/util/CMakeLists.txt b/programs/util/CMakeLists.txt
index f302de7..f9b6604 100644
--- a/programs/util/CMakeLists.txt
+++ b/programs/util/CMakeLists.txt
@@ -1,5 +1,5 @@
 set(libs
-     mbedtls
+    mbedtls
 )
 
 add_executable(strerror strerror.c)