libnvdimm, dimm: clear 'locked' status on successful DIMM enable

commit d34cb808 upstream.

If we successfully enable a DIMM then it must not be locked and we can
clear the label-read failure condition. Otherwise, we need to reload the
entire bus provider driver to achieve the same effect, and that can
disrupt unrelated DIMMs and namespaces.

Fixes: 9d62ed96 ("libnvdimm: handle locked label storage areas")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>