vdpa: Extend routine to accept vdpa device name

stable inclusion
from stable-v5.12
commit fd70a406
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5WXCZ
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=fd70a406a344e084ac680c3f14e71d37d6023883



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In a subsequent patch, when user initiated command creates a vdpa device,
the user chooses the name of the vdpa device.
To support it, extend the device allocation API to consider this name
specified by the caller driver.

Signed-off-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210105103203.82508-3-parav@nvidia.com


Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Pengyuan Zhao <zhaopengyuan@hisilicon.com>