wifi: mac80211: fix possible leak in ieee80211_tx_control_port()

Add missing dev_kfree_skb() in an error path in
ieee80211_tx_control_port() to avoid a memory leak.

Fixes: dd820ed6 ("wifi: mac80211: return error from control port TX for drops")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20220818043349.4168835-1-yangyingliang@huawei.com


Signed-off-by: Johannes Berg <johannes.berg@intel.com>