usb: dwc3: trace: print enqueue/dequeue pointers too

By printing enqueue/dequeue pointers, we can make sure that our TRB
handling is correct. We've had a recent situation where we were not
always dequeueing all TRBs in an SG list and this helped figure out
what the problem was.

Signed-off-by: Felipe Balbi <balbi@kernel.org>