ALSA: hda - Fix missing bass speaker on ASUS N550

ALSA: hda - Fix missing bass speaker on ASUS N550

commit a30c9aaa900a5fda21b90d5d6a3eaa3cbf16e330 upstream.

The laptop has a built-in speaker on NID 0x1a.  It's an LFE only on
the right channel, so we need to provide an explicit chmap, too.

There might be other surround speakers, but they can fixed in addition
at later point, so let's fix the easier bass speaker at first.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=65091
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>