Add missing ext3_journal_stop() in error handling.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>