Signed-off-by: NPavel Roskin <proski@gnu.org>

Fix memory leak and unneeded unlock in orinoco_join_ap()

If orinoco_lock() fails, the code would still run orinoco_unlock(),
instead of freeing the allocated memory.  Found by sparse.
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>