KVM: arm64: Don't retire MMIO instruction w/ pending (emulated) SError

KVM: arm64: Don't retire MMIO instruction w/ pending (emulated) SError

KVM might have an emulated SError queued for the guest if userspace
returned an abort for MMIO. Better yet, it could actually be a
*synchronous* exception in disguise if SCTLR2_ELx.EASE is set.

Don't advance PC if KVM owes an emulated SError, just like the handling
of emulated SEA injection.

Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250708172532.1699409-24-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>