fix(versal2): update check for TRANSFER_LIST macro

Replace #if defined(TRANSFER_LIST) by #if TRANSFER_LIST.
By default TRANSFER_LIST macro is defined with value 0 in Makefile.
So checking if the macro is defined will always be true and instead
need to check the value of the macro to add the conditional code.

Change-Id: I90b06f378326d5e03ad576377ad173e81b100f56
Signed-off-by: Akshay Belsare <akshay.belsare@amd.com>
diff --git a/plat/amd/versal2/include/platform_def.h b/plat/amd/versal2/include/platform_def.h
index 090fe46..42c9b08 100644
--- a/plat/amd/versal2/include/platform_def.h
+++ b/plat/amd/versal2/include/platform_def.h
@@ -91,7 +91,7 @@
 #define PLAT_OCM_BASE			U(0xBBF00000)
 #define PLAT_OCM_LIMIT			U(0xBC000000)
 
-#if defined(TRANSFER_LIST)
+#if TRANSFER_LIST
 /*
  * FIXME: This address should come from firmware before TF-A
  * Having this to make sure the transfer list functionality works