usb: gadget: udc: net2280: Re-enable dynamic debug messages

Some debug messages were not build due to unconditional #if 0.

These messages are very useful for debugging and the user can enable
them on demand via dynamic debug.

If they are not enabled the performance is not affected.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>