drm/amd/display: create plane rotation property for Bonaire and later

[Why]
DCE6 chipsets do not support HW rotation

[How]
rotation property is created for Bonaire and later

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Mauro Rossi <issor.oruam@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>