drm/i915: Extract mode_changed computation out of stage_output_config()
drm/i915: Extract mode_changed computation out of stage_output_config()

This should make the conversion to atomic easier, by splitting the
initialization of the atomic state from the logic that decides if a
modeset is needed.

Signed-off-by: Ander Conselvan de Oliveira <71330eafc99ba196752d2b2af84b34019e4104c2@intel.com>
Reviewed-by: Maarten Lankhorst <743c2818a341d71b99ed2b566f9f80c2fc288f93@linux.intel.com>
Signed-off-by: Daniel Vetter <c1b6782c4af8f0673da8923a0702a1832e5940f4@ffwll.ch>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs