qstr: constify instances in ocfs2

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/ocfs2/dlm/dlmdomain.c

@@ -172,12 +172,10 @@ void __dlm_unhash_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
 void __dlm_insert_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
 {
 	struct hlist_head *bucket;
-	struct qstr *q;
 
 	assert_spin_locked(&dlm->spinlock);
 
-	q = &res->lockname;
-	bucket = dlm_lockres_hash(dlm, q->hash);
+	bucket = dlm_lockres_hash(dlm, res->lockname.hash);
 
 	/* get a reference for our hashtable */
 	dlm_lockres_get(res);