ath10k: don't drop control and null func Rx

HTT_RX_IND_MPDU_STATUS_MGMT_CTRL was pretty greedy
and because of that ath10k ended up dropping
Control Frames as well as Null Func frames.

Reported-by: Okhwan Lee <ohlee@mwnl.snu.ac.kr>
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>