GFS2: Use seq_vprintf for glocks debugfs file

Make use of the newly added seq_vprintf() function.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>

fs/gfs2/glock.c

@@ -51,7 +51,6 @@ struct gfs2_glock_iter {
 	struct gfs2_sbd *sdp;		/* incore superblock           */
 	struct gfs2_glock *gl;		/* current glock struct        */
 	loff_t last_pos;		/* last position               */
-	char string[512];		/* scratch space               */
 };
 
 typedef void (*glock_examiner) (struct gfs2_glock * gl);
@@ -951,9 +950,7 @@ void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...)
 	va_start(args, fmt);
 
 	if (seq) {
-		struct gfs2_glock_iter *gi = seq->private;
-		vsprintf(gi->string, fmt, args);
-		seq_puts(seq, gi->string);
+		seq_vprintf(seq, fmt, args);
 	} else {
 		vaf.fmt = fmt;
 		vaf.va = &args;