drm/radeon: enable HDMI on DCE5 (AKA NI excluding Aruba)

After recent changes HDMI code is ready to be enabled on DCE5. This
patch just changes conditions to execute already present code on DCE5.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Tested-by: Christian König <christian.koenig@amd.com>
Tested-by: Andre Heider <a.heider@gmail.com>
Tested-by: Zoltán Böszörményi <zboszor@pr.hu>
Signed-off-by: Dave Airlie <airlied@redhat.com>