When PCI trx rings are reset, the DMA engine should also be reset.
Otherswise, the rx_tag of rx flow is not synchronous to hw.

Remove DMA reset when rtw_pci_start() as we added it in
rtw_pci_setup().
Signed-off-by: Chin-Yen Lee <timlee@realtek.com>
Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Reviewed-by: Chris Chiu <chiu@endlessm.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>