[GFS2] Make glock operations const

For all the usual reasons of enforcing correctness and potentially
reducing code size, this patch makes the glock operations const.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 77f0903..38098ac 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -130,7 +130,7 @@
 	void (*go_unlock) (struct gfs2_holder * gh);
 	void (*go_callback) (struct gfs2_glock * gl, unsigned int state);
 	void (*go_greedy) (struct gfs2_glock * gl);
-	int go_type;
+	const int go_type;
 };
 
 enum {
@@ -189,7 +189,7 @@
 	struct list_head gl_waiters2;	/* HIF_DEMOTE, HIF_GREEDY */
 	struct list_head gl_waiters3;	/* HIF_PROMOTE */
 
-	struct gfs2_glock_operations *gl_ops;
+	const struct gfs2_glock_operations *gl_ops;
 
 	struct gfs2_holder *gl_req_gh;
 	gfs2_glop_bh_t gl_req_bh;