To get a SPI_MAX_INTID, interrupt controller type Register
should be masked with ARM_GIC_ICDICTR_GET_SPI_RANGE.
However, since ARM_GIC_ICDICTR_SPI_RANGE_TO_MAX_INTID macro
uses ARM_GIC_ICDICTR_GET_EXT_SPI_RANGE mask,
it returns wrong SPI_MAX_INITID.
This makes a failure of loading GenericWatchDog in FVP RevC model.
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
Fixes: d6d2f68e38 ("ArmPkg/Drivers/ArmGicDxe: ...")