ALSA: hda: STAC_DELL_M6 EAPD

Add support for EAPD on system suspend and disabling EAPD on headphone jack
detection for STAC_DELL_M6 laptops.

This patch fixes the regressions, the silent output on HP of some Dell
laptops (see Novell bnc#446025):
	https://bugzilla.novell.com/show_bug.cgi?id=446025



Signed-off-by: Matthew Ranostay <mranostay@embeddedalley.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>