ALSA: hda: Move common haswell init to a helper

Geminilake vendor nid is different from other Skylake variants, but rest
of the initialization code is same.

So a variable is added in hdmi_spec to store the platform specific vendor
nid and move the initialization code to a helper function to be used by
both platform specific init.

Fixes: 126cfa2f ("ALSA: hda: Add Geminilake HDMI codec ID")
Signed-off-by: Ander Conselvan De Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Signed-off-by: Jaikrishna Nemallapudi <jaikrishnax.nemallapudi@intel.com>
Cc: Senthilnathan Veppur <senthilnathanx.veppur@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>