Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r258036:
Add IDs for the ASIX 88179 and 88178A USB to GigE adapters.

MFC r258331:
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.

MFC r258617 (by lwhsu):
Also note to add xhci(4) to kernel configuration to utilize USB 3.0

MFC r258618 (by lwhsu):
Mention axge(4)

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