vdpa: Avoid taking cf_mutex lock on get status

mainline inclusion
from mainline-v5.17-rc1
commit f6d955d8
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=f6d955d80830b6e6f6a170be68cc3628f36365dd



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Avoid the wrapper holding cf_mutex since it is not protecting anything.
To avoid confusion and unnecessary overhead incurred by it, remove.

Fixes: f489f27bc0ab ("vdpa: Sync calls set/get config/status with cf_mutex")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220111183400.38418-2-elic@nvidia.com


Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei <Liu&lt;si-wei.liu@oracle.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Pengyuan Zhao <zhaopengyuan@hisilicon.com>