These function pointers are missing from dcn30_init

.calc_vupdate_position : Used to help avoid cursor stuttering
.set_pipe : Needed for setting ABM

So add them
Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>