Revert "drm/i915: start adding dp mst audio"

This reverts 'commit 3708d5e0 ("drm/i915: start adding dp mst audio")'
because it breaks MST multi-monitor setups on some platforms.

Fixes: 3708d5e0 ("drm/i915: start adding dp mst audio")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97907


Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reported-by: Kim Lidström <kim@dxtr.im>
Cc: Libin Yang <libin.yang@linux.intel.com>
Cc: Lyude <cpaul@redhat.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1475132104-2754-1-git-send-email-dhinakaran.pandiyan@intel.com