ALSA: hda - Fix EAPD GPIO control for Sigmatel codecs

The EAPD GPIO is dynamically turned on/off for some machines with
Sigmatel codecs, but this didn't work as expected, and it resulted in
spontaneous lost of speaker outputs per HP plugging or power-saving.

This patch fixes the bug by simply including spec->eapd_mask into
spec->gpio_mask and spec->gpio_data bits.

Reported-and-tested-by: Eric Shattow <lucent@gmail.com>
Cc: <stable@vger.kernel.org> [v3.9+]
Signed-off-by: Takashi Iwai <tiwai@suse.de>