xfs: constify xfs_item_ops

The log item ops aren't nessecarily the biggest exploit vector, but marking
them const is easy enough.  Also remove the unused xfs_item_ops_t typedef
while we're at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>

diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index 603f3eb..3ae713c 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -326,7 +326,7 @@
 						 struct xfs_log_item *);
 							/* buffer item iodone */
 							/* callback func */
-	struct xfs_item_ops		*li_ops;	/* function list */
+	const struct xfs_item_ops	*li_ops;	/* function list */
 
 	/* delayed logging */
 	struct list_head		li_cil;		/* CIL pointers */
@@ -341,7 +341,7 @@
 	{ XFS_LI_IN_AIL,	"IN_AIL" }, \
 	{ XFS_LI_ABORTED,	"ABORTED" }
 
-typedef struct xfs_item_ops {
+struct xfs_item_ops {
 	uint (*iop_size)(xfs_log_item_t *);
 	void (*iop_format)(xfs_log_item_t *, struct xfs_log_iovec *);
 	void (*iop_pin)(xfs_log_item_t *);
@@ -352,7 +352,7 @@
 	void (*iop_push)(xfs_log_item_t *);
 	bool (*iop_pushbuf)(xfs_log_item_t *);
 	void (*iop_committing)(xfs_log_item_t *, xfs_lsn_t);
-} xfs_item_ops_t;
+};
 
 #define IOP_SIZE(ip)		(*(ip)->li_ops->iop_size)(ip)
 #define IOP_FORMAT(ip,vp)	(*(ip)->li_ops->iop_format)(ip, vp)