gpio: renesas: Add RZ/A1 R7S72100 GPIO driver

Add GPIO driver for RZ/A1 SoC. The IP is very different from the
R-Car Gen2/Gen3 one already present in the tree, hence a custom
driver.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Chris Brandt <chris.brandt@renesas.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 684ca9d..e36a8ab 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -169,6 +169,12 @@
 	help
 	  This driver supports the GPIO banks on Renesas RCar SoCs.
 
+config RZA1_GPIO
+	bool "Renesas RZ/A1 GPIO driver"
+	depends on DM_GPIO && RZA1
+	help
+	  This driver supports the GPIO banks on Renesas RZ/A1 R7S72100 SoCs.
+
 config ROCKCHIP_GPIO
 	bool "Rockchip GPIO driver"
 	depends on DM_GPIO