Need to also test for defined(${v}_${PROG})
Import the axge(4) driver for the ASIX AX88178A and AX88179 USB Ethernet
adapters. Both devices support Gigabit Ethernet and USB 2.0, and the AX88179
supports USB 3.0. The driver was written by kevlo@ and lwhsu@, with a few
bug fixes from me.

MFC after:	2 months
Regenerate usb.conf after r258331.
Provide the correct path to bus_autoconf.sh.