ath11k: vdev delete synchronization with firmware

When the interface is added immediately after removing the
interface, vdev deletion in firmware might not have been
completed.

Hence, add vdev_delete_resp_event and wait_event_timeout
to synchronize with firmware.

Signed-off-by: Ritesh Singh <ritesi@codeaurora.org>
Signed-off-by: Maharaja Kennadyrajan <mkenna@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1605514143-17652-2-git-send-email-mkenna@codeaurora.org