Fix behaviour in poor resource conditions. With this new patch,
tidied with indent and with SNDRV_PCM_TRIGGER_STOP being used.
Signed-off by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>