net80211: adjust a printf to toeee80211_note

Throughout net80211 there are multiple ways to log (debugging)
information. Start to clenaup one as I kept hitting it to harmonize
the output. The more we get away from printfs into either wrapper
functions or macros the more likely we can use holistic systematic
tracing in the future.

Sponsored by: The FreeBSD Foundation
MFC after: 3 days