feat(drtm): add platform functions for DRTM

Added platform hooks to retrieve DRTM features and
address map.
Additionally, implemented these hooks for the FVP platform.

Signed-off-by: John Powell <john.powell@arm.com>
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: I5621cc9807ffff8139ae8876250147f7b2c76759
diff --git a/bl31/bl31.mk b/bl31/bl31.mk
index ec70627..f435815 100644
--- a/bl31/bl31.mk
+++ b/bl31/bl31.mk
@@ -148,8 +148,9 @@
 endif
 
 ifeq (${DRTM_SUPPORT},1)
-BL31_SOURCES		+=	services/std_svc/drtm/drtm_main.c	\
-				services/std_svc/drtm/drtm_dma_prot.c	\
+BL31_SOURCES		+=	services/std_svc/drtm/drtm_main.c		\
+				services/std_svc/drtm/drtm_dma_prot.c		\
+				services/std_svc/drtm/drtm_res_address_map.c	\
 				${MBEDTLS_SOURCES}
 endif