USB: ci13xxx_udc: handle controllers with less than 16 EPs

The ci13xxx_udc driver checks the number of endpoints in the udc
controller, however some routines expect that the hardware has 16
bidirectional endpoints.

This patch improves the driver to work on controllers with less than
16 endpoints like the udc controller found on freescale's
mx23 and mx28.

Tested-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/ci13xxx_udc.h b/drivers/usb/gadget/ci13xxx_udc.h
index 2370777..f4871e1 100644
--- a/drivers/usb/gadget/ci13xxx_udc.h
+++ b/drivers/usb/gadget/ci13xxx_udc.h
@@ -127,7 +127,7 @@
 	struct ci13xxx_ep          ci13xxx_ep[ENDPT_MAX]; /* extended endpts */
 	u32                        ep0_dir;    /* ep0 direction */
 #define ep0out ci13xxx_ep[0]
-#define ep0in  ci13xxx_ep[16]
+#define ep0in  ci13xxx_ep[hw_ep_max / 2]
 	u8                         remote_wakeup; /* Is remote wakeup feature
 							enabled by the host? */
 	u8                         suspended;  /* suspended by the host */