ath10k: fix WPA crypto

Commit 370e5673 ("ath10k: fix broken traffic for 802.1x in client mode")
introduced a regression on WPA crypto. All keys were treated as if they were
WEP which resulted in WPA being incorrectly installed to fw/hw and subsequently
no traffic.

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