FROMLIST: KVM: arm64: Check if running in VHE from kvm_host_owns_hyp_mappings()

The kvm_host_owns_hyp_mappings() function should return true if and only
if the host kernel is responsible for creating the hypervisor stage-1
mappings. That is only possible in standard non-VHE mode, or during boot
in protected nVHE mode. But either way, non of this makes sense in VHE,
so make sure to catch this case as well, hence making the function
return sensible values in any context (VHE or not).

Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20211201170411.1561936-2-qperret@google.com
Bug: 209599700
Change-Id: Iec9d5f5f6f1258b76725df9b93064a9ddef1e670