[CIFS] Fix oops in cifs_create when nfsd server exports cifs mount

nfsd is passing null nameidata (probably the only one doing that)
on call to create - cifs was missing one check for this.

Note that running nfsd over a cifs mount requires specifying fsid on
the nfs exports entry and requires mounting cifs with serverino mount
option.

Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 38706e8..def89f2 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -264,7 +264,8 @@
 				direntry->d_op = &cifs_dentry_ops;
 			d_instantiate(direntry, newinode);
 		}
-		if ((nd->flags & LOOKUP_OPEN) == FALSE) {
+		if ((nd == NULL /* nfsd case - nfs srv does not set nd */) ||
+			((nd->flags & LOOKUP_OPEN) == FALSE)) {
 			/* mknod case - do not leave file open */
 			CIFSSMBClose(xid, pTcon, fileHandle);
 		} else if (newinode) {