ath10k: don't forget to replenish after fragmented Rx

In theory it was possible to drain entire HTT Rx
ring via fragmented Rx leading to Rx lockup.

In practice non-data traffic would always trigger
replenishment via the regular Rx handler.

For correctness sake make sure to replenish the
ring on fragmented Rx.

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