gma500: Convert Cedarview to work with new output handling

Replace psb_intel_output with psb_intel_encoder and psb_intel_connector.
Things will need to be cleaned up and tested so consider this an initial
patch for Cedarview.

Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>