Automatically switch to polling mode for CORB/RIRB communication
if the irq-driven mode seems not working well.  If the polling
mode still doesn't work, switch to single_cmd mode as fallback.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NJaroslav Kysela <perex@suse.cz>