MFC
Sync usb.conf file to head branch.
MFC r227751, r238766, r241553, r242748, r244047, r245947, r246021, r247255,
    r249039, r249204, r250848, r251351, r252295, r252498, r255123, r255238,
    r256782, r257132, r257390 and r259675:
- Add various new USB ID's and quirks.
- Make sure the usbdevs mergeinfo gets recorded on the sys directory.