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/plat/fvp/bl1_plat_setup.c b/plat/fvp/bl1_plat_setup.c
index 8fe4c95..f3176d5 100644
--- a/plat/fvp/bl1_plat_setup.c
+++ b/plat/fvp/bl1_plat_setup.c
@@ -139,8 +139,8 @@
 	}
 
 	configure_mmu(&bl1_tzram_layout,
-	              TZROM_BASE,
-	              TZROM_BASE + TZROM_SIZE,
-	              BL1_COHERENT_RAM_BASE,
-	              BL1_COHERENT_RAM_LIMIT);
+			TZROM_BASE,
+			TZROM_BASE + TZROM_SIZE,
+			BL1_COHERENT_RAM_BASE,
+			BL1_COHERENT_RAM_LIMIT);
 }