Move GIC setup to a separate file

GIC setup code which used to be in bl31_plat_setup.c is now in fvp_gic.c
to simplify future changes to other bootloader stages.  This patch moves
code from bl31_plat_setup.c to fvp_gic.c, simplifies the include file
list for bl31_plat_setup.c, moves GIC declarations from the bl31.h header
file into the platform.h, and reworks files according to coding style
guide.

Change-Id: I48d82a4ba33e7114dcc88f9ca98767a06cf8f417
diff --git a/bl31/bl31.mk b/bl31/bl31.mk
index fec09b8..4aed11b 100644
--- a/bl31/bl31.mk
+++ b/bl31/bl31.mk
@@ -43,7 +43,7 @@
 BL31_C_OBJS		:=	bl31_main.o bl31_plat_setup.o bl31_arch_setup.o	\
 				exception_handlers.o bakery_lock.o cci400.o 	\
 				fvp_common.o fvp_pm.o fvp_pwrc.o fvp_topology.o	\
-				runtime_svc.o gic_v2.o psci_setup.o		\
+				runtime_svc.o fvp_gic.o gic_v2.o psci_setup.o	\
 				psci_common.o psci_afflvl_on.o psci_main.o	\
 				psci_afflvl_off.o psci_afflvl_suspend.o