ARM: imx: remove mxc_iomux_v3_init() call from imx53_init_early()

Today, imx53 handles iomux configuration using pinctrl driver, so
mxc_iomux_v3_init() call in imx53_init_early() is there for nothing.
Remove the call from there.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

arch/arm/mach-imx/mm-imx5.c

@@ -89,15 +89,7 @@ void __init imx51_init_early(void)
 
 void __init imx53_init_early(void)
 {
-	struct device_node *np;
-	void __iomem *base;
-
 	mxc_set_cpu_type(MXC_CPU_MX53);
-
-	np = of_find_compatible_node(NULL, NULL, "fsl,imx53-iomuxc");
-	base = of_iomap(np, 0);
-	WARN_ON(!base);
-	mxc_iomux_v3_init(base);
 	imx_src_init();
 }