- Copy stable/10@296371 to releng/10.3 in preparation for 10.3-RC1
builds.
- Update newvers.sh to reflect RC1.
- Update __FreeBSD_version to reflect 10.3.
- Update default pkg(8) configuration to use the quarterly branch.

Approved by: re (implicit)

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

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

Bring over my AR9287 work in progress.

It isn't linked into the build because it's missing the TX power
and PDADC programming code.

This code is mostly based on the ath9k codebase, compared against
the Atheros codebase as appropriate.

What's implemented:

* probe/attach
* EEPROM board value programming
* RX initial calibration
* radio channel programming
* general MAC / baseband setup
* async fifo setup
* open-loop tx power calibration

What's missing before it can be enabled by default:

* TX power / calibration setting code
* closed-loop tx power calibration routines
* TSF2 handling
* generic timer support from ath9k

Obtained from: Atheros, ath9k