drivers: usb: nordic: Fix class/vendor request handling

SetAddress request (0x05) is ignored and not propagated, because it
is handled by nRF hardware. Curently, request type is not checked
causing class or vendor request 0x05 to be inappropiately ignored.
Only standard requests (type = 0) shoud be ignored. This commit
fixes the issue.

Signed-off-by: Paweł Zadrożniak <pawel.zadrozniak@nordicsemi.no>