ath-common: import common Atheros/QCA code This version is based on https://git.kernel.org/pub/scm/linux/kernel/git/kvalo/ath.git/log/?h=master 6bae9de622d3ef4805aba40e763eb4b0975c4f6d and was committed to FreeBSD main as ebacd8013fe5f7fdf9f6a5b286f6680dd2891036.