The per-tid statistics need to be released after the call to rdev_get_station

Cc: stable@vger.kernel.org
Fixes: 8689c051 ("cfg80211: dynamically allocate per-tid stats for station info")
Signed-off-by: NFelix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20200108170630.33680-2-nbd@nbd.nameSigned-off-by: NJohannes Berg <johannes.berg@intel.com>