arm64/sysreg: Add new system registers for GCS

FEAT_GCS introduces a number of new system registers. Add the registers
available up to EL2 to sysreg as per DDI0601 2022-12.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-13-45284e538474@kernel.org


Signed-off-by: Will Deacon <will@kernel.org>