ARM: imx: move EHCI platform defines out of platform_data header

The platform_data header usb-ehci-mxc.h has a lot of stuff used by only
IMX platform code.  They shouldn't be really in this header but a IMX
platform local header.  Create ehci.h and move these stuff into it.

Signed-off-by: Shawn Guo <shawn.guo@freescale.com>

arch/arm/mach-imx/mach-pcm037.c

@@ -45,6 +45,7 @@
 
 #include "common.h"
 #include "devices-imx31.h"
+#include "ehci.h"
 #include "hardware.h"
 #include "iomux-mx3.h"
 #include "pcm037.h"