TF-A GICv3 driver: Separate GICD and GICR accessor functions

This patch provides separation of GICD, GICR accessor
functions and adds new macros for GICv3 registers access
as a preparation for GICv3.1 and GICv4 support.
NOTE: Platforms need to modify to include both
'gicdv3_helpers.c' and 'gicrv3_helpers.c' instead of the
single helper file previously.

Change-Id: I1641bd6d217d6eb7d1228be3c4177b2d556da60a
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
diff --git a/plat/mediatek/mt8183/platform.mk b/plat/mediatek/mt8183/platform.mk
index 597e18b..59ffe5d 100644
--- a/plat/mediatek/mt8183/platform.mk
+++ b/plat/mediatek/mt8183/platform.mk
@@ -31,6 +31,8 @@
                    drivers/arm/gic/common/gic_common.c                   \
                    drivers/arm/gic/v3/arm_gicv3_common.c                 \
                    drivers/arm/gic/v3/gicv3_helpers.c                    \
+                   drivers/arm/gic/v3/gicdv3_helpers.c			 \
+                   drivers/arm/gic/v3/gicrv3_helpers.c			 \
                    drivers/arm/gic/v3/gic500.c                           \
                    drivers/arm/gic/v3/gicv3_main.c                       \
                    drivers/delay_timer/delay_timer.c                     \