usb - Update bus/u4b
* Update bus/u4b from FreeBSD to commit 3121e258c76aa, 10 March 2015,
with the following commit message:
Lock softc before clearing bits.
* Some bits not updated. Some changes around the MSI handling work
differently in DFly so I punted on that. And the serial/tty in FreeBSD
is a bit different, particular this 'pps' stuff.
* Numerous bits of code currently conditionalized out use ABI features
from FreeBSD, particularly RWTUN, which we do not yet have. Currently
non-critical, we can fix these as the related code gets used (if the
related code gets used).
Reviewed-by: Markus Pfeiffer
- [DB] sys/bus/u4b/input/uep.c