When skbs queued for each TX ring are relased in PCI stop flow,
the ring index should be reset at the same time.
Signed-off-by: Chin-Yen Lee <timlee@realtek.com> Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com> Signed-off-by: Kalle Valo <kvalo@codeaurora.org>