crypto: nx - constify vio_device_id

vio_device_id are not supposed to change at runtime. All functions
working with vio_device_id provided by <asm/vio.h> work with
const vio_device_id. So mark the non-const structs as const.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/nx/nx.c

@@ -833,7 +833,7 @@ static void __exit nx_fini(void)
 	vio_unregister_driver(&nx_driver.viodriver);
 }
 
-static struct vio_device_id nx_crypto_driver_ids[] = {
+static const struct vio_device_id nx_crypto_driver_ids[] = {
 	{ "ibm,sym-encryption-v1", "ibm,sym-encryption" },
 	{ "", "" }
 };