Build: Enable 'REGRESSION' for IPC model

Enable the execution of regression test suite with IPC model.

Change-Id: Ife2116df72159c2a57b3b99c37529431873650c8
Signed-off-by: Edison Ai <edison.ai@arm.com>
diff --git a/ConfigCoreIPCTfmLevel2.cmake b/ConfigCoreIPCTfmLevel2.cmake
index b0f0787..8592066 100644
--- a/ConfigCoreIPCTfmLevel2.cmake
+++ b/ConfigCoreIPCTfmLevel2.cmake
@@ -26,7 +26,7 @@
 ##These variables select how the projects are built. Each project will set
 #various project specific settings (e.g. what files to build, macro
 #definitions) based on these.
-set (REGRESSION False)
+set (REGRESSION True)
 set (CORE_TEST False)
 set (CORE_IPC True)