KVM: arm64: Introduce __pkvm_host_mkyoung_guest()

Plumb the kvm_pgtable_stage2_mkyoung() callback into pKVM for
non-protected guests. It will be called later from the fault handling
path.

Tested-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20241218194059.3670226-16-qperret@google.com


Signed-off-by: Marc Zyngier <maz@kernel.org>