pinctrl: mcp23s08: drop OF_GPIO dependency

The driver compiles & works perfectly fine without OF_GPIO on x86,
so lets drop the dependency.
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/Kconfig

@@ -148,7 +148,6 @@ config PINCTRL_FALCON
 
 config PINCTRL_MCP23S08
 	tristate "Microchip MCP23xxx I/O expander"
-	depends on OF_GPIO
 	depends on SPI_MASTER || I2C
 	select GPIOLIB_IRQCHIP
 	select REGMAP_I2C if I2C