usb: gadget: net2280: check interrupts for all endpoints

USB3380 in enhanced mode has 4 IN and 4 OUT endpoints. Check
interrupts for all of them.

Tested-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>