ALSA: hda - Move vmaster TLV parsing to snd_hda_gen_parse_auto_config()

Add vmaster_tlv[] to hda_gen_spec and store the suggested TLV data
in snd_hda_gen_parse_auto_config().  This allows the codec driver to
correct the TLV data (e.g. mute capability) before actually creating
vmaster instance.

Signed-off-by: Takashi Iwai <tiwai@suse.de>