feat(rdn2): enable extended SPI support

Enable the GIC_EXT_INTID configuration to support extended interrupt
IDs for RD-N2 multichip platform.

Signed-off-by: Vivek Gautam <vivek.gautam@arm.com>
Change-Id: Ic8d59ba0e692e5f13f3cdeffc64d76cd4741aa11
1 file changed