Build: Introduce TFM_CONFIG_USE_TRUSTZONE

Both CMake variable and C define.
Default to ON, set to OFF in appropriate platform configs.
Used to control inclusion of veneers, etc.

Change-Id: Ic1abb17fc6c5b8ac23b5dff09b52aef4946b6f94
Signed-off-by: Chris Brand <chris.brand@cypress.com>
diff --git a/interface/CMakeLists.txt b/interface/CMakeLists.txt
index a38bd9c..b02cc11 100644
--- a/interface/CMakeLists.txt
+++ b/interface/CMakeLists.txt
@@ -48,6 +48,7 @@
         $<$<BOOL:${TFM_PSA_API}>:TFM_PSA_API>
         $<$<BOOL:${CONFIG_TFM_ENABLE_CTX_MGMT}>:CONFIG_TFM_ENABLE_CTX_MGMT>
         $<$<BOOL:${TFM_ISOLATION_LEVEL}>:TFM_LVL=${TFM_ISOLATION_LEVEL}>
+        $<$<BOOL:${TFM_CONFIG_USE_TRUSTZONE}>:TFM_CONFIG_USE_TRUSTZONE>
         $<$<BOOL:${TFM_MULTI_CORE_TOPOLOGY}>:TFM_MULTI_CORE_TOPOLOGY>
         $<$<BOOL:${FORWARD_PROT_MSG}>:FORWARD_PROT_MSG=${FORWARD_PROT_MSG}>
         $<$<BOOL:${CONFIG_TFM_PARTITION_META}>:CONFIG_TFM_PARTITION_META>