Remove support for legacy VE memory map in FVP

This patch removes support for legacy Versatile Express memory map for the
GIC peripheral in the FVP platform. The user guide is also updated for the
same.

Change-Id: Ib8cfb819083aca359e5b46b5757cb56cb0ea6533
diff --git a/plat/arm/common/arm_gicv3_legacy.c b/plat/arm/common/arm_gicv3_legacy.c
index 6170933..8396b60 100644
--- a/plat/arm/common/arm_gicv3_legacy.c
+++ b/plat/arm/common/arm_gicv3_legacy.c
@@ -48,7 +48,7 @@
  * In the GICv3 Legacy mode, the Group 1 secure interrupts are treated as Group
  * 0 interrupts.
  */
-const unsigned int irq_sec_array[] = {
+static const unsigned int irq_sec_array[] = {
 	PLAT_ARM_G0_IRQS,
 	PLAT_ARM_G1S_IRQS
 };