feat(arm_fpga): support GICv4 images

Up until now we relied on the GICs used in our FPGA images to be GICv3
compliant, without the "direct virtual injection" feature (aka GICv4)
To support newer images which have GICv4 compliant GICs, enable the
newly introduced GICv4 detection code, and use that also when we adjust
the redistributor region size in the devicetree.

This allows the same BL31 image to be used with GICv3 or GICv4 FPGA

Change-Id: I9f6435a6d5150983625efe3650a8b7d1ef11b1d1
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
4 files changed