Revert "usb: gadget: net2280: Add support for PLX USB338X"

This reverts commit c4128cac.

This should come through Felipe's tree first, and there was a bunch of
other patches that are needed after this one as well that I didn't have.

Cc: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>