ath10k: improve warm reset reliability

Warm reset is now able to recover after device
crashes which required a cold reset before.

This should greatly reduce chances of getting data
bus errors or host system freezes due to buggy
cold reset on some chips.

kvalo: use ath10k_pci_soc_*()

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