ArmPkg/ArmGic: Use the GIC Redistributor instead of GIC Distributor for GICv3

ArmPkg/ArmGic: Use the GIC Redistributor instead of GIC Distributor for GICv3

GICv3 controller with no GICv2 legacy support must use the GIC
Redistributor registers instead of the GIC Distributor registers
for some operations (eg: enable/disable interrupts).

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>
Tested-by: Ard Biesheuvel <ard@linaro.org>
Reviewed-by: Ard Biesheuvel <ard@linaro.org>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16874 6f19259b-4bc3-4df7-8a09-765794883524