ath10k: change static wep key handling for client mode

mac80211 sets static WEP keys as groupwise while
firmware requires them to be installed twice as
both pairwise and groupwise.

Until now these keys were installed once as
pairwise only and, due to that special handling,
needed additional tricks to support 802.1x as
well.

Without this patch in some cases (when AP and
ath10k client use different default tx keys)
multicast communication was broken.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>