M28: Fix OB1 bug in GPIO driver

This patch fixes a small off-by-one bug in the GPIO driver for the mxs platform that allowed the selection gpio pins of one bank more than the SoC actually has.

Signed-off-by: Robert Deliën <robert at delien.nl>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
diff --git a/drivers/gpio/mxs_gpio.c b/drivers/gpio/mxs_gpio.c
index b7e9591..539738b 100644
--- a/drivers/gpio/mxs_gpio.c
+++ b/drivers/gpio/mxs_gpio.c
@@ -120,7 +120,7 @@
 
 int gpio_request(int gp, const char *label)
 {
-	if (PAD_BANK(gp) > PINCTRL_BANKS)
+	if (PAD_BANK(gp) >= PINCTRL_BANKS)
 		return -EINVAL;
 
 	return 0;