libnvdimm: handle locked label storage areas

Per the latest version of the "NVDIMM DSM Interface Example" [1], the
label data retrieval routine can report a "locked" status. In this case
all regions associated with that DIMM are disabled until the label area
is unlocked. Provide generic libnvdimm enabling for NVDIMMs with label
data area locking capabilities.

[1]: http://pmem.io/documents/

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/nvdimm/dimm.c

@@ -49,6 +49,8 @@ static int nvdimm_probe(struct device *dev)
 	kref_init(&ndd->kref);
 
 	rc = nvdimm_init_nsarea(ndd);
+	if (rc == -EACCES)
+		nvdimm_set_locked(dev);
 	if (rc)
 		goto err;