ALSA: hda - Fix mute-LED GPIO initialization for IDT codecs

The IDT codecs initializes the GPIO setup for mute LEDs via
snd_hda_sync_vmaster_hook().  This works in most cases except for the
very first call, which is called before PCM and control creations.
Thus before Master switch is set manually via alsactl, the mute LED
may show the wrong state, depending on the polarity.

Now it's fixed by calling the LED-status update function manually when
no vmaster is set yet.

Cc: <stable@vger.kernel.org> [v3.4+]
Signed-off-by: Takashi Iwai <tiwai@suse.de>