plat/fvp: Populate GICv3 parameters dynamically

Query the GICD and GICR base addresses in runtime using fconf getter
APIs.

Signed-off-by: Lauren Wehrmeister <lauren.wehrmeister@arm.com>
Change-Id: I309fb2874f3329ddeb8677ddb53ed4c02199a1e9
diff --git a/plat/arm/board/fvp/platform.mk b/plat/arm/board/fvp/platform.mk
index 04cebca..a88ec13 100644
--- a/plat/arm/board/fvp/platform.mk
+++ b/plat/arm/board/fvp/platform.mk
@@ -65,6 +65,10 @@
 				plat/common/plat_gicv3.c		\
 				plat/arm/common/arm_gicv3.c
 
+	ifeq ($(filter 1,${BL2_AT_EL3} ${RESET_TO_BL31} ${RESET_TO_SP_MIN}),)
+		FVP_GIC_SOURCES += plat/arm/board/fvp/fvp_gicv3.c
+	endif
+
 else ifeq (${FVP_USE_GIC_DRIVER}, FVP_GICV2)
 
 # No GICv4 extension