pinctrl: Declare operation structures as const

The pinconf, pinctrl and pinmux operation structures hold function
pointers that are never modified. Declare them as const.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/pinctrl-sirf.c b/drivers/pinctrl/pinctrl-sirf.c
index d02498b..0990a721 100644
--- a/drivers/pinctrl/pinctrl-sirf.c
+++ b/drivers/pinctrl/pinctrl-sirf.c
@@ -979,7 +979,7 @@
 	kfree(map);
 }
 
-static struct pinctrl_ops sirfsoc_pctrl_ops = {
+static const struct pinctrl_ops sirfsoc_pctrl_ops = {
 	.get_groups_count = sirfsoc_get_groups_count,
 	.get_group_name = sirfsoc_get_group_name,
 	.get_group_pins = sirfsoc_get_group_pins,
@@ -1181,7 +1181,7 @@
 	return 0;
 }
 
-static struct pinmux_ops sirfsoc_pinmux_ops = {
+static const struct pinmux_ops sirfsoc_pinmux_ops = {
 	.enable = sirfsoc_pinmux_enable,
 	.disable = sirfsoc_pinmux_disable,
 	.get_functions_count = sirfsoc_pinmux_get_funcs_count,