Add some more usbdevs from the NetBSD sources.
Robert Sprowson authored
In particular, the SMSC ethernet controller and hub on the Beagleboard
xm.
Changed pointer assignments & comparisons with 0 to be NULL for clarity.
Implement a left trim function for any printed out strings obtained from
the device (to mirror usbd_trim_spaces) so that when dopey manufacturers
use a space instead of their company name everything lines up still.

Version 0.68. Tagged as 'NetBSD-0_68'
1b44a876