ath10k: finally kill htt_rx_info

Struct htt_rx_info is not needed anymore while
we will use ieee80211_rx_status structure as
a template.

Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>