Cards like the multiface/digiface have additional headphones out. Those
were not initialized in the presets due to wrong loop boundaries:
maxdest represents the amount of physical stereo pairs, and chnls is
either equal or less, so the output fader array needs more iterations
than the playback section.
Signed-off-by: Adrian Knoth <adi@drcomp.erfurt.thur.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>