HACK: gfx: display: Double the tc35876x pixel clock

HACK: gfx: display: Double the tc35876x pixel clock

The pixel clock and vertical refresh values the driver reports for the
internal display are wrong. The page flip logic needs accurate clock
information to convert time intervals to scanline intervals.

Double the pixel clock in the tc35876x driver so that the values are
at least a little closer to reality.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>