pinctrl: mxs: register driver at postcore_initcall time

It's not so usual, but there are still some cases which require pinctrl
driver function at arch_initcall time.  So register imx23 and imx28
pinctrl driver at postcore_initcall time.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Richard Zhao <richard.zhao@freescale.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-imx23.c

@@ -292,7 +292,7 @@ static int __init imx23_pinctrl_init(void)
 {
 	return platform_driver_register(&imx23_pinctrl_driver);
 }
-arch_initcall(imx23_pinctrl_init);
+postcore_initcall(imx23_pinctrl_init);
 
 static void __exit imx23_pinctrl_exit(void)
 {

drivers/pinctrl/pinctrl-imx28.c

@@ -408,7 +408,7 @@ static int __init imx28_pinctrl_init(void)
 {
 	return platform_driver_register(&imx28_pinctrl_driver);
 }
-arch_initcall(imx28_pinctrl_init);
+postcore_initcall(imx28_pinctrl_init);
 
 static void __exit imx28_pinctrl_exit(void)
 {