agp: sis: constify pci_device_id.

pci_device_id are not supposed to change at runtime. All functions
working with pci_device_id provided by <linux/pci.h> work with
const pci_device_id. So mark the non-const structs as const.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/char/agp/sis-agp.c b/drivers/char/agp/sis-agp.c
index 2c74038..14909fc 100644
--- a/drivers/char/agp/sis-agp.c
+++ b/drivers/char/agp/sis-agp.c
@@ -237,7 +237,7 @@
 
 #endif /* CONFIG_PM */
 
-static struct pci_device_id agp_sis_pci_table[] = {
+static const struct pci_device_id agp_sis_pci_table[] = {
 	{
 		.class		= (PCI_CLASS_BRIDGE_HOST << 8),
 		.class_mask	= ~0,