mac80211: Do not report false error from mesh_path_add.

In case the hash grow failed, it is not fair to return error -
the new node _was_ _actually_ added in this case.

Besides, after my previous patch, this grow is more likely
to fail on large hashes.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/mac80211/mesh_pathtbl.c

@@ -206,7 +206,7 @@ int mesh_path_add(u8 *dst, struct net_device *dev)
 		newtbl = mesh_table_grow(mesh_paths);
 		if (!newtbl) {
 			write_unlock(&pathtbl_resize_lock);
-			return -ENOMEM;
+			return 0;
 		}
 		rcu_assign_pointer(mesh_paths, newtbl);
 		write_unlock(&pathtbl_resize_lock);