mfd: Constify i2c_device_id tables

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Harald Welte <laforge@gnumonks.org>
Cc: Matti Aaltonen <matti.j.aaltonen@nokia.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/wl1273-core.c b/drivers/mfd/wl1273-core.c
index f76f6c7..04914f2 100644
--- a/drivers/mfd/wl1273-core.c
+++ b/drivers/mfd/wl1273-core.c
@@ -25,7 +25,7 @@
 
 #define DRIVER_DESC "WL1273 FM Radio Core"
 
-static struct i2c_device_id wl1273_driver_id_table[] = {
+static const struct i2c_device_id wl1273_driver_id_table[] = {
 	{ WL1273_FM_DRIVER_NAME, 0 },
 	{ }
 };