pinctrl: pinctrl-imx: add imx51 pinctrl driver

ChangeLog v1->v2:
* change PIN_FUNC_ID base in binding doc to 0 from 1.
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NStephen Warren <swarren@wwwdotorg.org>
Signed-off-by: NDong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/Kconfig

@@ -31,6 +31,14 @@ config PINCTRL_IMX
 	select PINMUX
 	select PINCONF
 
+config PINCTRL_IMX51
+	bool "IMX51 pinctrl driver"
+	depends on OF
+	depends on SOC_IMX51
+	select PINCTRL_IMX
+	help
+	  Say Y here to enable the imx51 pinctrl driver
+
 config PINCTRL_IMX53
 	bool "IMX53 pinctrl driver"
 	depends on OF

drivers/pinctrl/Makefile

@@ -10,6 +10,7 @@ obj-$(CONFIG_PINCTRL)		+= devicetree.o
 endif
 obj-$(CONFIG_GENERIC_PINCONF)	+= pinconf-generic.o
 obj-$(CONFIG_PINCTRL_IMX)	+= pinctrl-imx.o
+obj-$(CONFIG_PINCTRL_IMX51)	+= pinctrl-imx51.o
 obj-$(CONFIG_PINCTRL_IMX53)	+= pinctrl-imx53.o
 obj-$(CONFIG_PINCTRL_IMX6Q)	+= pinctrl-imx6q.o
 obj-$(CONFIG_PINCTRL_PXA3xx)	+= pinctrl-pxa3xx.o