nfc: pn544: constify i2c_device_id

i2c_device_id are not supposed to change at runtime. All functions
working with i2c_device_id provided by <linux/i2c.h> work with
const i2c_device_id. So mark the non-const structs as const.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/nfc/pn544/i2c.c

@@ -54,7 +54,7 @@
 #define PN544_HCI_I2C_LLC_MAX_SIZE	(PN544_HCI_I2C_LLC_LEN_CRC + 1 + \
 					 PN544_HCI_I2C_LLC_MAX_PAYLOAD)
 
-static struct i2c_device_id pn544_hci_i2c_id_table[] = {
+static const struct i2c_device_id pn544_hci_i2c_id_table[] = {
 	{"pn544", 0},
 	{}
 };