wireless-drivers fixes for 4.20 Last set of fixes for 4.20. All (except the mt76 fix) of these are important fixes to user reported problems and pretty small in size. rtlwifi * fix skb leak mwifiex * revert a commit from v4.19 due to problems with locking mt76 * fix a potential NULL derenfence * add entry to MAINTAINERS iwlwifi * fix a firmware crash which was a regression introduced in v4.20-rc4 ath10k * fix a firmware crash with wcn3990 firmware