CVE-2022-48861 vdpa: fix use-after-free on vp_vdpa_remove

In the Linux kernel, the following vulnerability has been resolved:

vdpa: fix use-after-free on vp_vdpa_remove

When vp_vdpa driver is unbind, vp_vdpa is freed in vdpa_unregister_device
and then vp_vdpa->mdev.pci_dev is dereferenced in vp_modern_remove,
triggering use-after-free.

Call Trace of unbinding driver free vp_vdpa :
do_syscall_64
vfs_write
kernfs_fop_write_iter
device_release_driver_internal
pci_device_remove
vp_vdpa_remove
vdpa_unregister_device
kobject_release
device_release
kfree

Call Trace of dereference vp_vdpa->mdev.pci_dev:
vp_modern_remove
pci_release_selected_regions
pci_release_region
pci_resource_len
pci_resource_end
(dev)->resource[(bar)].end