With this in place, we can start converting pieces of the modeset code
to look at the connector atomic state instead of the staged config.

v2: Handle the load detect staged config changes too. (Ander)
    Remove unnecessary blank line. (Daniel)
Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>