cmake: Move generation of test_certs.h to mbedtls

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 64d95dc..70706a6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -416,6 +416,26 @@
          ${CMAKE_CURRENT_SOURCE_DIR}/tests/src/test_helpers/*.c)
     add_library(mbedtls_test_helpers OBJECT ${MBEDTLS_TEST_HELPER_FILES})
     set_base_compile_options(mbedtls_test_helpers)
+
+    if(GEN_FILES)
+        add_custom_command(
+            OUTPUT
+                ${MBEDTLS_DIR}/tests/src/test_certs.h
+            WORKING_DIRECTORY
+                ${MBEDTLS_DIR}/tests
+            COMMAND
+                "${MBEDTLS_PYTHON_EXECUTABLE}"
+                "${MBEDTLS_FRAMEWORK_DIR}/scripts/generate_test_cert_macros.py"
+                "--output"
+                "${MBEDTLS_DIR}/tests/src/test_certs.h"
+            DEPENDS
+                ${MBEDTLS_FRAMEWORK_DIR}/scripts/generate_test_cert_macros.py
+        )
+        add_custom_target(mbedtls_test_certs_header
+            DEPENDS ${MBEDTLS_DIR}/tests/src/test_certs.h)
+        add_dependencies(mbedtls_test_helpers mbedtls_test_certs_header)
+    endif()
+
     target_include_directories(mbedtls_test_helpers
         PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/framework/tests/include
         PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/tests/include
diff --git a/tf-psa-crypto/CMakeLists.txt b/tf-psa-crypto/CMakeLists.txt
index d30b787..a16e205 100644
--- a/tf-psa-crypto/CMakeLists.txt
+++ b/tf-psa-crypto/CMakeLists.txt
@@ -420,23 +420,9 @@
             DEPENDS
                 ${MBEDTLS_FRAMEWORK_DIR}/scripts/generate_test_keys.py
         )
-        add_custom_target(tf_psa_crypto_test_keys_header DEPENDS ${MBEDTLS_FRAMEWORK_DIR}/tests/src/test_keys.h)
-
-        add_custom_command(
-            OUTPUT
-                ${MBEDTLS_DIR}/tests/src/test_certs.h
-            WORKING_DIRECTORY
-                ${MBEDTLS_DIR}/tests
-            COMMAND
-                "${TF_PSA_CRYPTO_PYTHON_EXECUTABLE}"
-                "${MBEDTLS_FRAMEWORK_DIR}/scripts/generate_test_cert_macros.py"
-                "--output"
-                "${MBEDTLS_DIR}/tests/src/test_certs.h"
-            DEPENDS
-                ${MBEDTLS_FRAMEWORK_DIR}/scripts/generate_test_cert_macros.py
-        )
-        add_custom_target(tf_psa_crypto_test_certs_header DEPENDS ${MBEDTLS_DIR}/tests/src/test_certs.h)
-        add_dependencies(tf_psa_crypto_test tf_psa_crypto_test_keys_header tf_psa_crypto_test_certs_header)
+        add_custom_target(tf_psa_crypto_test_keys_header
+            DEPENDS ${MBEDTLS_FRAMEWORK_DIR}/tests/src/test_keys.h)
+        add_dependencies(tf_psa_crypto_test tf_psa_crypto_test_keys_header)
     endif()
     target_include_directories(tf_psa_crypto_test
         PRIVATE ${MBEDTLS_FRAMEWORK_DIR}/tests/include