ALSA: pcm: Set missing stop_operating flag at undoing trigger start

ALSA: pcm: Set missing stop_operating flag at undoing trigger start

[ Upstream commit 5c8cc93b06d1ff860327a273abf3ac006290d242 ]

When a PCM trigger-start fails at snd_pcm_do_start(), PCM core tries
to undo the action at snd_pcm_undo_start() by issuing the trigger STOP
manually.  At that point, we forgot to set the stop_operating flag,
hence the sync-stop won't be issued at the next prepare or other
calls.

This patch adds the missing stop_operating flag at
snd_pcm_undo_start().

Fixes: 1e850beea278 ("ALSA: pcm: Add the support for sync-stop operation")
Link: https://lore.kernel.org/r/b4e71631-4a94-613-27b2-fb595792630@carlh.net
Link: https://lore.kernel.org/r/20221205132124.11585-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>