Expose FPMR in the signal context on systems where it is supported. The
kernel validates the exact size of the FPSIMD registers so we can't readily
add it to fpsimd_context without disruption.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240306-arm64-2023-dpisa-v5-4-c568edc8ed7f@kernel.orgSigned-off-by: Catalin Marinas <catalin.marinas@arm.com>