ath10k: remove transfer_id from ath10k_hif_cb::tx_completion

Pass the eid argument via skbuff control buffer.
This will make it possible to work with queues of
HTC event buffers.

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