JFS: avoid assert in lbmfree

In the error path, lmLogInit must clear log->lbuf_free before
calling lbmFree.
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>

fs/jfs/jfs_logmgr.c

@@ -1435,6 +1435,8 @@ int lmLogInit(struct jfs_log * log)
 	 *      unwind on error
 	 */
       errout30:		/* release log page */
+	log->wqueue = NULL;
+	bp->l_wqnext = NULL;
 	lbmFree(bp);
 
       errout20:		/* release log superblock */