Build: Move configurations into a specified directory

Configurations are increasing and cause root directory looks not very
clear. Move configurations into a specified directory. Related changes
in projects need to be made due to config file change. And create fake
config files with the same name under the root directory, link to the
config files under 'configs' to provide compatibility temporarily.

Change-Id: I420b7a567e96d6540b5cd9697b08575d89274fe4
Signed-off-by: Ken Liu <ken.liu@arm.com>
diff --git a/docs/user_guides/tfm_build_instruction.rst b/docs/user_guides/tfm_build_instruction.rst
index 4097b71..fd21f7b 100644
--- a/docs/user_guides/tfm_build_instruction.rst
+++ b/docs/user_guides/tfm_build_instruction.rst
@@ -19,7 +19,7 @@
        | <file> is the absolute path to configurations file
          named as ``Config<APP_NAME>.cmake``.
        | i.e. On Linux:
-         ``-DPROJ_CONFIG=`readlink -f ../ConfigRegression.cmake```
+         ``-DPROJ_CONFIG=`readlink -f ../configs/ConfigRegression.cmake```
 
    * - -DTARGET_PLATFORM=<target platform name>
      - Specifies the target platform.
@@ -103,7 +103,7 @@
     cd trusted-firmware-m
     mkdir cmake_test
     cd cmake_test
-    cmake -G"Unix Makefiles" -DPROJ_CONFIG=`readlink -f ../ConfigRegression.cmake` -DTARGET_PLATFORM=AN521 -DCOMPILER=ARMCLANG ../
+    cmake -G"Unix Makefiles" -DPROJ_CONFIG=`readlink -f ../configs/ConfigRegression.cmake` -DTARGET_PLATFORM=AN521 -DCOMPILER=ARMCLANG ../
     cmake --build ./ -- install
 
 *TF-M build regression tests on Windows*
@@ -114,7 +114,7 @@
     cd trusted-firmware-m
     mkdir cmake_test
     cd cmake_test
-    cmake -G"Unix Makefiles" -DPROJ_CONFIG=`cygpath -am ../ConfigRegression.cmake` -DTARGET_PLATFORM=AN521 -DCOMPILER=ARMCLANG ../
+    cmake -G"Unix Makefiles" -DPROJ_CONFIG=`cygpath -am ../configs/ConfigRegression.cmake` -DTARGET_PLATFORM=AN521 -DCOMPILER=ARMCLANG ../
     cmake --build ./ -- install
 
 Build for PSA API compliance tests
@@ -138,7 +138,7 @@
     cd trusted-firmware-m
     mkdir cmake_psa_test
     cd cmake_psa_test
-    cmake -G"Unix Makefiles" -DPROJ_CONFIG=`readlink -f ../ConfigPsaApiTest.cmake` -DPSA_API_TEST_CRYPTO -DTARGET_PLATFORM=AN521 -DCOMPILER=ARMCLANG ../
+    cmake -G"Unix Makefiles" -DPROJ_CONFIG=`readlink -f ../configs/ConfigPsaApiTest.cmake` -DPSA_API_TEST_CRYPTO -DTARGET_PLATFORM=AN521 -DCOMPILER=ARMCLANG ../
     cmake --build ./ -- install
 
 Location of build artifacts