Bluetooth: btintel: Constify static struct regmap_bus

The only usage of regmap_ibt is to (after the regmap_init() macro is
expanded), pass its address to __regmap_init(), which takes a pointer to
const struct regmap_bus as input. Make it const to allow the compiler to
put it in read-only memory.
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

drivers/bluetooth/btintel.c

@@ -794,7 +794,7 @@ static void regmap_ibt_free_context(void *context)
 	kfree(context);
 }
 
-static struct regmap_bus regmap_ibt = {
+static const struct regmap_bus regmap_ibt = {
 	.read = regmap_ibt_read,
 	.write = regmap_ibt_write,
 	.gather_write = regmap_ibt_gather_write,