virtio_pci_modern: hide vp_modern_get_queue_notify_off()

mainline inclusion
from mainline-v5.13-rc1
commit a5f7a24f
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5WXCZ
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a5f7a24f49d81fab9f59611814a8817cc8a876a2



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All users (both virtio-pci library and vp_vdpa driver) has been
switched to use vp_modern_map_vq_notify(). So there's no need to
export the low level helper of vp_modern_get_queue_notify_off().

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210415073147.19331-5-jasowang@redhat.com


Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
Signed-off-by: Pengyuan Zhao <zhaopengyuan@hisilicon.com>