ath11k: Cleanup in pdev destroy and mac register during crash on recovery

Debugfs pdev entries should be cleaned up during the crash
on recovery. If not, mac register will fail for the reason
that it is already registered during core reconfigure.

Signed-off-by: Maharaja Kennadyrajan <mkenna@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1586538405-16226-1-git-send-email-mkenna@codeaurora.org