ALSA: hda - Add hdmi chmap verb programming ops to chmap object

Add slot and channel count programming to hdmi_chmap object and
move the chmap_ops to core. Use register_chmap_ops API to
register for default ops.  Override specific chmap ops in the
driver.

Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>