pinctrl: Move for_each_maps() to namespace and hide iterator inside

First of all, while for_each_maps() is private to pin control subsystem
it's still better to have it put into a namespace.

Besides that, users are not relying on iterator variable, so hide it
inside for-loop.

Signed-off-by: Andy Shevchenko <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Linus Walleij <[e-mail]>

drivers/pinctrl/core.c

···
 	struct pinctrl *p;
 	const char *devname;
 	struct pinctrl_maps *maps_node;
-	int i;
 	const struct pinctrl_map *map;
 	int ret;
 
···
 
 	mutex_lock(&pinctrl_maps_mutex);
 	/* Iterate over the pin control maps to locate the right ones */
-	for_each_maps(maps_node, i, map) {
+	for_each_pin_map(maps_node, map) {
 		/* Map must be for this device */
 		if (strcmp(map->dev_name, devname))
 			continue;
···
 static int pinctrl_maps_show(struct seq_file *s, void *what)
 {
 	struct pinctrl_maps *maps_node;
-	int i;
 	const struct pinctrl_map *map;
 
 	seq_puts(s, "Pinctrl maps:\n");
 
 	mutex_lock(&pinctrl_maps_mutex);
-	for_each_maps(maps_node, i, map) {
+	for_each_pin_map(maps_node, map) {
 		seq_printf(s, "device %s\nstate %s\ntype %s (%d)\n",
 			   map->dev_name, map->name, map_type(map->type),
 			   map->type);

drivers/pinctrl/core.h

···
 extern struct mutex pinctrl_maps_mutex;
 extern struct list_head pinctrl_maps;
 
-#define for_each_maps(_maps_node_, _i_, _map_) \
-	list_for_each_entry(_maps_node_, &pinctrl_maps, node) \
-		for (_i_ = 0, _map_ = &_maps_node_->maps[_i_]; \
-			_i_ < _maps_node_->num_maps; \
-			_i_++, _map_ = &_maps_node_->maps[_i_])
+#define for_each_pin_map(_maps_node_, _map_)						\
+	list_for_each_entry(_maps_node_, &pinctrl_maps, node)				\
+		for (unsigned int __i = 0;						\
+		     __i < _maps_node_->num_maps && (_map_ = &_maps_node_->maps[__i]);	\
+		     __i++)