kernel/usb4bsd: Switch to generating usbdevs{,_data}.h during the build.

Taken-from: FreeBSD
kernel/usb4bsd: Remove the Makefile for usbdevs{,_data}.h generation.
kernel: Remove another syslink related file which was forgotten earlier.

Approved-by: dillon
kernel: Remove some unused lines from 'files' files.
kernel: Add 'targ' and 'targbh' devices to the LINT configs.