arm64/sysreg: add PIR*_ELx registers

Add definitions of PIR_EL1, PIR_EL12, PIRE0_EL1, PIRE0_EL12, and
PIR_EL2 registers.

Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20230606145859.697944-5-joey.gouly@arm.com


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>