ide: constify struct ide_port_info

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/pci/cmd64x.c b/drivers/ide/pci/cmd64x.c
index ae01319..ea0143e 100644
--- a/drivers/ide/pci/cmd64x.c
+++ b/drivers/ide/pci/cmd64x.c
@@ -548,7 +548,7 @@
 	}
 }
 
-static struct ide_port_info cmd64x_chipsets[] __devinitdata = {
+static const struct ide_port_info cmd64x_chipsets[] __devinitdata = {
 	{	/* 0 */
 		.name		= "CMD643",
 		.init_chipset	= init_chipset_cmd64x,