KVM: arm64: Condition HW AF updates on config option

KVM: arm64: Condition HW AF updates on config option

[ Upstream commit 1dfc3e905089a0bcada268fb5691a605655e0319 ]

As it currently stands, KVM makes use of FEAT_HAFDBS unconditionally.
Use of the feature in the rest of the kernel is guarded by an associated
Kconfig option.

Align KVM with the rest of the kernel and only enable VTCR_HA when
ARM64_HW_AFDBM is enabled. This can be helpful for testing changes to
the stage-2 access fault path on Armv8.1+ implementations.

Link: https://lore.kernel.org/r/20221202185156.696189-7-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Stable-dep-of: 6df696cd9bc1 ("arm64: errata: Mitigate Ampere1 erratum AC03_CPU_38 at stage-2")
Signed-off-by: Sasha Levin <sashal@kernel.org>