wifi: Fixes for ns-3.42
- Fix failing EHT network regression run on MacOS
- Fix Block Ack agreement establishment in the 6 GHz band
- Minstrel HT does not return HT rates if operating in the 6 GHz band
- Fix crash when calling WifiMacHelper::SetFrameExchangeManager()
- Avoid peeking packets when there is no mask for the given link