ALSA: intel8x0: Mute External Amplifier by default for another Sony model

BugLink: https://bugs.launchpad.net/bugs/474972

This Sony model needs External Amplifier muted 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>