mwifiex: pcie: stop setting/clearing 'surprise_removed'

These are already handled by mwifiex_shutdown_sw() and
mwifiex_reinit_sw(). Ideally, we'll kill the flag entirely eventually,
as I suspect it breeds race conditions.

Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>