ALSA: hda - Allow analog low-current mode when dynamic power-control is on

VIA codecs have several different power-saving features, and one of
them is the analog low-current mode.  But it turned out that the ALC
mode causes pop-noises at each on/off time on some machines.  As a
quick workaround, disable the ALC when another power-saving feature,
the dynamic pin power-control, is turned off, too, since the dynamic
power-control is already exposed as a mixer enum element so that user
can turn it on/off freely.

Bugzilla: https://bugzilla.novell.com/show_bug.cgi?id=741128

Cc: <stable@kernel.org> [v3.1+]
Signed-off-by: Takashi Iwai <tiwai@suse.de>