Build: Merge tfm_partition_defs into tfm_config

CMake target tfm_partition_defs is merged into tfm_config. Same change
is also needed in tf-m-tests.

Signed-off-by: Xinyu Zhang <xinyu.zhang@arm.com>
Change-Id: I79dc74d5acfc73a290f1288e3c0ecd76ab81be85
diff --git a/test/secure_fw/secure_tests.cmake b/test/secure_fw/secure_tests.cmake
index c16b8d1..64cf607 100644
--- a/test/secure_fw/secure_tests.cmake
+++ b/test/secure_fw/secure_tests.cmake
@@ -58,7 +58,7 @@
 target_link_libraries(tfm_s_tests
     INTERFACE
         tfm_test_framework_s
-        tfm_partition_defs
+        tfm_config
         tfm_spm
 )