When passing the DP/HDMI/SDVO registers to the encoder init functions,
include the VLV specific offset in the value.

v2: Resolved conflicts w/ VLV SDVO elimination
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>