drm/i915: Include the scanline offset in the state dump

When looking at raw hardware scanline numbers it's helpful to
remember what the offset between the hardware values and our
more human readable numbers should be. Include that in the state dump.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241210211007.5976-9-ville.syrjala@linux.intel.com


Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>