ARM: config: Remove not needed CONFIG_MXC_USB_PORT define

After i.MX5's EHCI conversion to DM, the CONFIG_MXC_USB_PORT is not needed
anymore and should be removed.

Signed-off-by: Lukasz Majewski <lukma@denx.de>
diff --git a/include/configs/kp_imx53.h b/include/configs/kp_imx53.h
index 9bbf590..d09608d 100644
--- a/include/configs/kp_imx53.h
+++ b/include/configs/kp_imx53.h
@@ -17,7 +17,6 @@
 
 /* USB Configs */
 #define CONFIG_USB_EHCI_MX5
-#define CONFIG_MXC_USB_PORT	1
 #define CONFIG_MXC_USB_PORTSC	(PORT_PTS_UTMI | PORT_PTS_PTW)
 #define CONFIG_MXC_USB_FLAGS	0