Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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

- Update 6000 firmware to 9.221.4.1
- Add 6050 firmware

MFC after: 2 weeks

Update firmware for the 6000 series Intel cards to version 9.193.4.1.

Approved by: rpaulo (mentor)
MFC after: 2 weeks

iwn(4) update. Notable changes:
* new firmware
* untested support for 1000 and 6000 series
* bgscan support
* remove unnecessary RXON changes
* allow setting of country/regdomain by enforcing channel flags read
from the EEPROM
* suspend/resume fixes
* RF kill switch fixes
* LED adjustments
* several bus_dma*() related fixes
* addressed some LORs
* many other bug fixes

Submitted by: Bernhard Schmidt <bschmidt at techwires.net>
Obtained from: Brandon Gooch <jamesbrandongooch at gmail dot com> (LED
related changes), Benjamin Kaduk <kaduk at mit dot edu>
(LOR fixes), OpenBSD