pinctrl: imx1 core driver

Core driver for register formats of imx1/imx21/imx27 processors.

The pins of those processors are grouped into ports. Each port has 32
pins. The pins mux configuration is controlled by registers with 1 or 2
bit per pin, depending on the specific control register.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index e283c49..fcc748f 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -109,6 +109,11 @@
 	select PINMUX
 	select PINCONF
 
+config PINCTRL_IMX1_CORE
+	bool
+	select PINMUX
+	select PINCONF
+
 config PINCTRL_IMX35
 	bool "IMX35 pinctrl driver"
 	depends on OF