usb: musb: fix bug in musb_cleanup_urb

Control transfers with data expected from device to host will use usb_rcvctrlpipe()
for urb->pipe so for such urbs 'is_in' will be set causing control urb to fall
into the first "if" condition in musb_cleanup_urb().

Fixed by adding logic to check for non control endpoints.

Signed-off-by: Ajay Kumar Gupta <ajay.gupta@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>