drm/amd/display: expose hwseq functions and add registers

drm/amd/display: expose hwseq functions and add registers

Make these functions non static and define registers for future use

	is_lower_pipe_tree_visible();
	is_upper_pipe_tree_visible();
	is_pipe_tree_visible();
	dcn10_program_pte_vm();
	set_hdr_multiplier();
	update_dchubp_dpp()
	find_top_pipe_for_stream()

Signed-off-by: Nevenko Stupar <Nevenko.Stupar@amd.com>
Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>