Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

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

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

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

Add AR5413 radar parameters and strong signal diversity capability.

This is a re-implementation based on the reference carrier code
for the AR5413.

Tested:
* Pulse detection for AR5212 and AR5413, to ensure the
correct behaviour for both chips

PR: kern/170904
Obtained from: Qualcomm Atheros

Replace Id keyword with FreeBSD keyword and set the svn props correctly.
No functional change.

add FreeBSD property

import ath hal

Update to later code from my repository:
o many bug fixes
o add new periodic calibration api
o break up 5416 periodic calibration code in preparation for 928x
o move get noise floor to rf backends
o 5416-specific ani (still disabled)
o modularize 5210 eeprom format a la other eeprom formats
o start cleaning up regdomain code
o prepare for proper 1/2 and 1/4 width channel support
o bring back 900MHz card support
o clean up 5212 rf version handling
o add 1/2 and 1/4 width channel support for 5212 parts
o split 5212 rfgain handling out
o improve ani debugging
o add AH_USE_INIPDGAIN compile option
o purge a bunch of dead 5212 state
o add 1/2 and 1/4 rate modes
o remove HAL_CAP_CHAN_HALFRATE and HAL_CAP_CHAN_QUARTERRATE; the
same info can now be deduced from the set of supported modes

virgin import of ath hal