change ieee80211_mhz2ieee to use the PSB mapping when the frequency falls in the proper place, not when we're handed a 1/2 or 1/4-rate channel
change ieee80211_mhz2ieee to use the PSB mapping when the frequency
falls in the proper place, not when we're handed a 1/2 or 1/4-rate channel

MFC after:	2 weeks

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase