Attest: Remove redundant definitions of PSA_INITIAL_ATTEST_MAX_TOKEN_SIZE

Create a initial_attestation.h template to set use case specific
PSA_INITIAL_ATTEST_MAX_TOKEN_SIZE value in build runtime.
Call CMake configure_file() to set PSA_INITIAL_ATTEST_MAX_TOKEN_SIZE
macro in initial_attestation.h, according to TF-M CMake config value.
Enforce builds to include generated initial_attestation.h, instead of
region_defs.h.
Remove platform specific definitions from platform region_defs.h.

Signed-off-by: David Hu <david.hu@arm.com>
Change-Id: Ibf7e09c8d1196401a44aeadf0c46802168d89b33
diff --git a/cmake/install.cmake b/cmake/install.cmake
index 5d516b9..ac42715 100644
--- a/cmake/install.cmake
+++ b/cmake/install.cmake
@@ -90,7 +90,7 @@
 endif()
 
 if (TFM_PARTITION_INITIAL_ATTESTATION)
-    install(FILES       ${INTERFACE_INC_DIR}/psa/initial_attestation.h
+    install(FILES       ${CMAKE_BINARY_DIR}/generated/interface/include/psa/initial_attestation.h
             DESTINATION ${INSTALL_INTERFACE_INC_DIR}/psa)
     install(FILES       ${INTERFACE_INC_DIR}/tfm_attest_defs.h
                         ${INTERFACE_INC_DIR}/tfm_attest_iat_defs.h