jfs: Simplify code

Calling 'list_splice' followed by 'INIT_LIST_HEAD' is equivalent to
'list_splice_init'.

This has been spotted with the following coccinelle script:
/////
@@
expression y,z;
@@

-   list_splice(y,z);
-   INIT_LIST_HEAD(y);
+   list_splice_init(y,z);

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>

fs/jfs/jfs_txnmgr.c

@@ -2893,8 +2893,7 @@ void txQuiesce(struct super_block *sb)
 	 * on anon_list2.  Let's check.
 	 */
 	if (!list_empty(&TxAnchor.anon_list2)) {
-		list_splice(&TxAnchor.anon_list2, &TxAnchor.anon_list);
-		INIT_LIST_HEAD(&TxAnchor.anon_list2);
+		list_splice_init(&TxAnchor.anon_list2, &TxAnchor.anon_list);
 		goto restart;
 	}
 	TXN_UNLOCK();