pinctrl: mvebu: constify mvebu_mpp_ctrl structures

As the mvebu_mpp_ctrl structures contain function pointers, it is
preferable for these to be made read-only to prevent the function
pointers being modified.  So make these const.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/mvebu/pinctrl-armada-370.c b/drivers/pinctrl/mvebu/pinctrl-armada-370.c
index 9cc1cc3..3cb6b4e 100644
--- a/drivers/pinctrl/mvebu/pinctrl-armada-370.c
+++ b/drivers/pinctrl/mvebu/pinctrl-armada-370.c
@@ -384,7 +384,7 @@ static const struct of_device_id armada_370_pinctrl_of_match[] = {
 	{ },
 };
 
-static struct mvebu_mpp_ctrl mv88f6710_mpp_controls[] = {
+static const struct mvebu_mpp_ctrl mv88f6710_mpp_controls[] = {
 	MPP_FUNC_CTRL(0, 65, NULL, armada_370_mpp_ctrl),
 };