ALSA: hda: remove an unused field from struct hda_codec

The .jacks field in struct hda_codec is unused and seems to be a
duplicate of .jacktbl, remove it.

Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>