[package] [docs] implement doth (802.11h) and wmm (802.11e) options for...

[package] [docs] implement doth (802.11h) and wmm (802.11e) options for broadcom as well; update docs


git-svn-id: svn://svn.openwrt.org/openwrt/trunk@17676 3c298f89-4303-0410-b956-a3cf2f4a3e73