wifi: mac80211: mesh: release the channel if start fails

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: mesh: release the channel if start fails ieee80211_join_mesh() acquires a channel context and then calls ieee80211_start_mesh(), which can fail. In that case, the chanctx isn't released then interface removal will attempt to unassign it after it's removed from the driver, hitting: wlan0: Failed check-sdata-in-driver check, flags: 0x0 WARNING: net/mac80211/driver-ops.c:366 at drv_unassign_vif_chanctx ieee80211_assign_link_chanctx __ieee80211_link_release_channel ieee80211_link_release_channel ieee80211_teardown_sdata unregister_netdevice_many_notify _cfg80211_unregister_wdev ieee80211_remove_interfaces ieee80211_unregister_hw mac80211_hwsim_del_radio hwsim_exit_net Correctly release the channel on start failures.

Where it's fixed