gpio: aggregator: Stop using ARCH_NR_GPIOS

ARCH_NR_GPIOS is used locally in aggr_parse() as the maximum number
of GPIOs to be aggregated together by the driver since
commit ec75039 ("gpio: aggregator: Use bitmap_parselist() for
parsing GPIO offsets").

Don't rely on the total possible number of GPIOs in the system but
define a local arbitrary macro for that, set to 512 which should be
large enough as it is also the default value for ARCH_NR_GPIOS.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

drivers/gpio/gpio-aggregator.c

@@ -23,6 +23,7 @@
 #include <linux/spinlock.h>
 #include <linux/string.h>
 
+#define AGGREGATOR_MAX_GPIOS 512
 
 /*
  * GPIO Aggregator sysfs interface
@@ -64,7 +65,7 @@ static int aggr_parse(struct gpio_aggregator *aggr)
 	unsigned int i, n = 0;
 	int error = 0;
 
-	bitmap = bitmap_alloc(ARCH_NR_GPIOS, GFP_KERNEL);
+	bitmap = bitmap_alloc(AGGREGATOR_MAX_GPIOS, GFP_KERNEL);
 	if (!bitmap)
 		return -ENOMEM;
 
@@ -84,13 +85,13 @@ static int aggr_parse(struct gpio_aggregator *aggr)
 		}
 
 		/* GPIO chip + offset(s) */
-		error = bitmap_parselist(offsets, bitmap, ARCH_NR_GPIOS);
+		error = bitmap_parselist(offsets, bitmap, AGGREGATOR_MAX_GPIOS);
 		if (error) {
 			pr_err("Cannot parse %s: %d\n", offsets, error);
 			goto free_bitmap;
 		}
 
-		for_each_set_bit(i, bitmap, ARCH_NR_GPIOS) {
+		for_each_set_bit(i, bitmap, AGGREGATOR_MAX_GPIOS) {
 			error = aggr_add_gpio(aggr, name, i, &n);
 			if (error)
 				goto free_bitmap;