net80211: move IEEE80211_F_WME check to vap for consistency

The IEEE80211_F_WME checks done on the ic were changed to be per-vap
back in the time when multi-bss was introduced or earlier in 2008.
This one was left out but given it is a (re-)accos-req case I see
no reason not to use the vap value here for consistency too.

Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Reviewed by: adrian
Differential Revision: https://reviews.freebsd.org/D36733