cifs: smbd: Only queue work for error recovery on memory registration

cifs: smbd: Only queue work for error recovery on memory registration

BugLink: https://bugs.launchpad.net/bugs/1858427
commit c21ce58eab1eda4c66507897207e20c82e62a5ac upstream.

It's not necessary to queue invalidated memory registration to work queue, as
all we need to do is to unmap the SG and make it usable again. This can save
CPU cycles in normal data paths as memory registration errors are rare and
normally only happens during reconnection.

Signed-off-by: Long Li <longli@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>