ath6kl: Fix multiple clients associating in AP mode

When one client is associated and connected to an ar6003 hw version
2.0 with firmware 3.1.1.149, and another client tries to connect, the
first client's MAC address is lost in the station list because the
"aid" is always "1".  The structure "wmi_connect_event" has the "aid"
as the second byte in the message, but it should be the first byte.

This patch has been tested with linux-3.10.40

Signed-off-by: Brent Taylor <motobud@gmail.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>