build(drtm): add DRTM support build option

Added DRTM support build option in the makefiles.
This build option will be used by the DRTM implementation
in the subsequent patches.

Signed-off-by: Manish V Badarkhe <manish.badarkhe@arm.com>
Signed-off-by: Lucian Paul-Trifu <lucian.paultrifu@gmail.com>
Change-Id: I15366f86b3ebd6ab2ebcb192753015d547cdddee

Makefile

@@ -833,6 +833,10 @@ ifeq (${CTX_INCLUDE_FPREGS},1)
     endif
 endif
 
+ifeq ($(DRTM_SUPPORT),1)
+    $(info DRTM_SUPPORT is an experimental feature)
+endif
+
 ################################################################################
 # Process platform overrideable behaviour
 ################################################################################
@@ -1008,6 +1012,7 @@ $(eval $(call assert_booleans,\
         HW_ASSISTED_COHERENCY \
         INVERTED_MEMMAP \
         MEASURED_BOOT \
+        DRTM_SUPPORT \
         NS_TIMER_SWITCH \
         OVERRIDE_LIBC \
         PL011_GENERIC_UART \
@@ -1144,6 +1149,7 @@ $(eval $(call add_defines,\
         HW_ASSISTED_COHERENCY \
         LOG_LEVEL \
         MEASURED_BOOT \
+        DRTM_SUPPORT \
         NS_TIMER_SWITCH \
         PL011_GENERIC_UART \
         PLAT_${PLAT} \

make_helpers/defaults.mk

@@ -463,3 +463,6 @@ TWED_DELAY			:= 0
 
 # By default, disable the mocking of RSS provided services
 PLAT_RSS_NOT_SUPPORTED		:= 0
+
+# Dynamic Root of Trust for Measurement support
+DRTM_SUPPORT			:= 0