usb: cdns3: gadget: improve the dump TRB operation at cdns3_ep_run_transfer

It only dumps the first TRB per request, it is not useful if only dump
the first TRB when there are several TRBs per request. We improve it by
dumpping all TRBs per request in this commit.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>