pinctrl: add __rcu annotations to fix sparse warnings

Sparse reports "warning: incorrect type in assignment (different
address spaces)".
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/core.c

@@ -686,7 +686,7 @@ EXPORT_SYMBOL_GPL(pinctrl_generic_remove_group);
 static void pinctrl_generic_free_groups(struct pinctrl_dev *pctldev)
 {
 	struct radix_tree_iter iter;
-	void **slot;
+	void __rcu **slot;
 
 	radix_tree_for_each_slot(slot, &pctldev->pin_group_tree, &iter, 0)
 		radix_tree_delete(&pctldev->pin_group_tree, iter.index);

drivers/pinctrl/pinmux.c

@@ -833,7 +833,7 @@ EXPORT_SYMBOL_GPL(pinmux_generic_remove_function);
 void pinmux_generic_free_functions(struct pinctrl_dev *pctldev)
 {
 	struct radix_tree_iter iter;
-	void **slot;
+	void __rcu **slot;
 
 	radix_tree_for_each_slot(slot, &pctldev->pin_function_tree, &iter, 0)
 		radix_tree_delete(&pctldev->pin_function_tree, iter.index);