isdn: mISDN: w6692: 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.

File size before:
   text	   data	    bss	    dec	    hex	filename
  13959	   4080	     24	  18063	   468f isdn/hardware/mISDN/w6692.o

File size After adding 'const':
   text	   data	    bss	    dec	    hex	filename
  14087	   3952	     24	  18063	   468f isdn/hardware/mISDN/w6692.o
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/isdn/hardware/mISDN/w6692.c

@@ -1398,7 +1398,7 @@ w6692_remove_pci(struct pci_dev *pdev)
 			pr_notice("%s: drvdata already removed\n", __func__);
 }
 
-static struct pci_device_id w6692_ids[] = {
+static const struct pci_device_id w6692_ids[] = {
 	{ PCI_VENDOR_ID_DYNALINK, PCI_DEVICE_ID_DYNALINK_IS64PH,
 	  PCI_ANY_ID, PCI_ANY_ID, 0, 0, (ulong)&w6692_map[0]},
 	{ PCI_VENDOR_ID_WINBOND2, PCI_DEVICE_ID_WINBOND2_6692,