sh-pfc: Replace first_gpio and last_gpio with nr_gpios

The SoC information first_gpio field is always equal to 0, and the
last_gpio field is the index of the last entry in the pinmux_gpios
array. Replace the first_gpio and last_gpio fields by a nr_gpios field,
and initialize it to ARRAY_SIZE(pinmux_gpios).

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/sh-pfc/pfc-sh7269.c b/drivers/pinctrl/sh-pfc/pfc-sh7269.c
index 87cb693..2013f4f 100644
--- a/drivers/pinctrl/sh-pfc/pfc-sh7269.c
+++ b/drivers/pinctrl/sh-pfc/pfc-sh7269.c
@@ -2822,10 +2822,9 @@
 	.mark = { PINMUX_MARK_BEGIN, PINMUX_MARK_END },
 	.function = { PINMUX_FUNCTION_BEGIN, PINMUX_FUNCTION_END },
 
-	.first_gpio = GPIO_PA1,
-	.last_gpio = GPIO_FN_LCD_M_DISP,
-
 	.gpios = pinmux_gpios,
+	.nr_gpios = ARRAY_SIZE(pinmux_gpios),
+
 	.cfg_regs = pinmux_config_regs,
 	.data_regs = pinmux_data_regs,