ath6kl: Send own IP addr to the firmware during WOW suspend

Firmware ARP module requires own IP addr in order to respond
to the outside world when the target is in WOW suspend state.

At present, firmware ARP module has capability to hold 2 IP addr.
So, WOW mode will be disabled if the total IP addr configured in
net_dev for our device is greater than firmware limit (MAX_IP_ADDRS)
which is 2 at this moment.

Signed-off-by: Raja Mani <rmani@qca.qualcomm.com>
Signed-off-by: Thirumalai Pachamuthu <tpachamu@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>