KVM: arm64: vgic: Drop vgic_check_ioaddr()

There are no more users of vgic_check_ioaddr(). Move its checks to
vgic_check_iorange() and then remove it.

Signed-off-by: Ricardo Koller <ricarkol@google.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211005011921.437353-6-ricarkol@google.com