pata_pdc2027x : make pdc2027x_*_timing structures const

Make these pdc2027x_*_timing structures const as it is never modified.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

drivers/ata/pata_pdc2027x.c

@@ -82,7 +82,7 @@ static int pdc2027x_set_mode(struct ata_link *link, struct ata_device **r_failed
  * is issued to the device. However, if the controller clock is 133MHz,
  * the following tables must be used.
  */
-static struct pdc2027x_pio_timing {
+static const struct pdc2027x_pio_timing {
 	u8 value0, value1, value2;
 } pdc2027x_pio_timing_tbl[] = {
 	{ 0xfb, 0x2b, 0xac }, /* PIO mode 0 */
@@ -92,7 +92,7 @@ static struct pdc2027x_pio_timing {
 	{ 0x23, 0x09, 0x25 }, /* PIO mode 4, IORDY on, Prefetch off */
 };
 
-static struct pdc2027x_mdma_timing {
+static const struct pdc2027x_mdma_timing {
 	u8 value0, value1;
 } pdc2027x_mdma_timing_tbl[] = {
 	{ 0xdf, 0x5f }, /* MDMA mode 0 */
@@ -100,7 +100,7 @@ static struct pdc2027x_mdma_timing {
 	{ 0x69, 0x25 }, /* MDMA mode 2 */
 };
 
-static struct pdc2027x_udma_timing {
+static const struct pdc2027x_udma_timing {
 	u8 value0, value1, value2;
 } pdc2027x_udma_timing_tbl[] = {
 	{ 0x4a, 0x0f, 0xd5 }, /* UDMA mode 0 */