arm64 patch: gicv3 support

This patch add gicv3 support to uboot armv8 platform.

Changes for v2:
  - rename arm/cpu/armv8/gic.S with arm/lib/gic_64.S
  - move smp_kick_all_cpus() from gic.S to start.S, it would be
    implementation dependent.
  - Each core initialize it's own ReDistributor instead of master
    initializeing all ReDistributors. This is advised by arnab.basu
    <arnab.basu@freescale.com>.

Signed-off-by: David Feng <fenghua@phytium.com.cn>
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index 9fc81cd..e035d6a 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -35,6 +35,7 @@
 
 obj-y	+= sections.o
 ifdef CONFIG_ARM64
+obj-y	+= gic_64.o
 obj-y	+= interrupts_64.o
 else
 obj-y	+= interrupts.o