regulator: dbx500: use seq_puts() instead of seq_printf()

For a constant format without additional arguments, use seq_puts()
instead of seq_printf(). Also, it fixes the following checkpatch
warning.

  WARNING: Prefer seq_puts to seq_printf
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

drivers/regulator/dbx500-prcmu.c

@@ -129,9 +129,9 @@ static int ux500_regulator_status_print(struct seq_file *s, void *p)
 	int i;
 
 	/* print dump header */
-	err = seq_printf(s, "ux500-regulator status:\n");
+	err = seq_puts(s, "ux500-regulator status:\n");
 	if (err < 0)
-		dev_err(dev, "seq_printf overflow\n");
+		dev_err(dev, "seq_puts overflow\n");
 
 	err = seq_printf(s, "%31s : %8s : %8s\n", "current",
 		"before", "after");