ata: declare ata_port_info structures as const

ata_port_info structures are either copied to other objects or their
references are stored in objects of type const. So, ata_port_info
structures having similar usage pattern can be made const.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

drivers/ata/pata_rdc.c

@@ -292,7 +292,7 @@ static struct ata_port_operations rdc_pata_ops = {
 	.prereset		= rdc_pata_prereset,
 };
 
-static struct ata_port_info rdc_port_info = {
+static const struct ata_port_info rdc_port_info = {
 
 	.flags		= ATA_FLAG_SLAVE_POSS,
 	.pio_mask	= ATA_PIO4,

drivers/ata/pata_sch.c

@@ -81,7 +81,7 @@ static struct ata_port_operations sch_pata_ops = {
 	.set_dmamode		= sch_set_dmamode,
 };
 
-static struct ata_port_info sch_port_info = {
+static const struct ata_port_info sch_port_info = {
 	.flags		= ATA_FLAG_SLAVE_POSS,
 	.pio_mask	= ATA_PIO4,
 	.mwdma_mask	= ATA_MWDMA2,

drivers/ata/sata_inic162x.c

@@ -737,7 +737,7 @@ static struct ata_port_operations inic_port_ops = {
 	.port_start		= inic_port_start,
 };
 
-static struct ata_port_info inic_port_info = {
+static const struct ata_port_info inic_port_info = {
 	.flags			= ATA_FLAG_SATA | ATA_FLAG_PIO_DMA,
 	.pio_mask		= ATA_PIO4,
 	.mwdma_mask		= ATA_MWDMA2,

drivers/ata/sata_via.c

@@ -166,7 +166,7 @@ static const struct ata_port_info vt6420_port_info = {
 	.port_ops	= &vt6420_sata_ops,
 };
 
-static struct ata_port_info vt6421_sport_info = {
+static const struct ata_port_info vt6421_sport_info = {
 	.flags		= ATA_FLAG_SATA,
 	.pio_mask	= ATA_PIO4,
 	.mwdma_mask	= ATA_MWDMA2,
@@ -174,7 +174,7 @@ static struct ata_port_info vt6421_sport_info = {
 	.port_ops	= &vt6421_sata_ops,
 };
 
-static struct ata_port_info vt6421_pport_info = {
+static const struct ata_port_info vt6421_pport_info = {
 	.flags		= ATA_FLAG_SLAVE_POSS,
 	.pio_mask	= ATA_PIO4,
 	/* No MWDMA */
@@ -182,7 +182,7 @@ static struct ata_port_info vt6421_pport_info = {
 	.port_ops	= &vt6421_pata_ops,
 };
 
-static struct ata_port_info vt8251_port_info = {
+static const struct ata_port_info vt8251_port_info = {
 	.flags		= ATA_FLAG_SATA | ATA_FLAG_SLAVE_POSS,
 	.pio_mask	= ATA_PIO4,
 	.mwdma_mask	= ATA_MWDMA2,