mtd: pci: 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: Boris Brezillon <boris.brezillon@free-electrons.com>

drivers/mtd/maps/pci.c

@@ -228,7 +228,7 @@ static struct mtd_pci_info intel_dc21285_info = {
  * PCI device ID table
  */
 
-static struct pci_device_id mtd_pci_ids[] = {
+static const struct pci_device_id mtd_pci_ids[] = {
 	{
 		.vendor =	PCI_VENDOR_ID_INTEL,
 		.device =	0x530d,