- Use bit twiddling macro to set IEEE80211_MODE_11A
- On the RT3572 chipset, there's no need to configure BBP register 86
Remove a couple of unused macros.
Somewhat mimic how the devel/subversion port prepopulates
'Sponsored by:' in the FreeBSD commit template.

Support for this has already existed ^/head/contrib/subversion
but it was not enabled in usr.bin/svn/svn/Makefile.

To use the pre-populated 'Sponsored by:' entry, set ORGANIZATION
in make.conf(5), for example:

    ORGANIZATION=   "The FreeBSD Foundation"

Reviewed by:	peter
Sponsored by:	The FreeBSD Foundation