ath10k: cleanup copy engine send completion

The physical address necessary to unmap DMA ('bufferp') is stored
in ath10k_skb_cb as 'paddr'. ath10k doesn't rely on the meta/transfer_id
when handling send completion (htc ep id is stored in sk_buff control
buffer). So the unused output arguments {bufferp, nbytesp and transfer_idp}
are removed from CE send completion. This change is needed before removing
the shadow copy of copy engine (CE) descriptors in follow up patch.

Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>