virito_pci libray: hide vp_modern_map_capability()

mainline inclusion
from mainline-v5.13-rc1
commit fd466b36
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=fd466b36940b22a506265edf12714bd0cf9ed836



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No user now and the capability should not be setup
externally. Instead, every access to the capability should be done via
virtio_pci_modern_device.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210415073147.19331-6-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>