ALSA: hda - Yet another fix for broken HSW HDMI pin connections

A Haswell test machine showed that the invalid connection list, but
this time it has only a single pin on the codec, thus the former fixup
code doesn't work as it assumes the three pins blindly.

This patch splits the former fixup code to two parts:
- Enable eDP 1.2 for Haswell codec
- Fix the connection list of pins on Haswell codec;
  the converter list is recorded dynamically in hdmi_add_cvt(), and
  applied in hdmi_add_pin()

Signed-off-by: Mengdong Lin <mengdong.lin@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>