arm64: Allow the user to select the max SVE vector length

Add a new flag, --sve-max-vl, which allows the user to specify an SVE
vector length for the VM. Just zero out unsupported VLs from what KVM
supports rather than cooking up the bitmap from scratch.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240620165702.1134918-2-oliver.upton@linux.dev
Signed-off-by: Will Deacon <will@kernel.org>
3 files changed