ALSA: intel8x0 - Mute External Amplifier by default for Sony VAIO VGN-B1VP

BugLink: https://bugs.launchpad.net/bugs/410933



This Sony VAIO model also needs External Amplifier unmuted for audible
playback, so make sure we set the inv_eapd quirk.

Signed-off-by: Daniel T Chen <crimsun@ubuntu.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>