drm/amd/display: correct stream LTE_340MCSC_SCRAMBLE value

[Why]
HDMI 2.0 requires scrambling under specific conditions. We refer to
stream property LTE_340MCSC_SCRAMBLE to determine whether en/dis
scrambling.
While creating stream for sink, we setup LTE_340MCSC_SCRAMBLE by
referring to edid_caps. However, dm_helpers_parse_edid_caps()
doesn't construct HDMI Forum block data for edid_caps.
Moreover, fill_stream_properties_from_drm_display_mode() aslo
unconsciously clear the LTE_340MCSC_SCRAMBLE flag.

[How]
Drm already provides drm_display_info to refer HDMI Forum vsdb info.
Set stream LTE_340MCSC_SCRAMBLE by drm_display_info and remove
memset in fill_stream_properties_from_drm_display_mode()
Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -3398,7 +3398,6 @@ static void fill_stream_properties_from_drm_display_mode(
 	struct amdgpu_dm_connector *aconnector = to_amdgpu_dm_connector(connector);
 	struct hdmi_vendor_infoframe hv_frame;
 	struct hdmi_avi_infoframe avi_frame;
-	memset(timing_out, 0, sizeof(struct dc_crtc_timing));
 
 	timing_out->h_border_left = 0;
 	timing_out->h_border_right = 0;
@@ -3662,6 +3661,9 @@ create_stream_for_sink(struct amdgpu_dm_connector *aconnector,
 
 	stream->dm_stream_context = aconnector;
 
+	stream->timing.flags.LTE_340MCSC_SCRAMBLE =
+		drm_connector->display_info.hdmi.scdc.scrambling.low_rates;
+
 	list_for_each_entry(preferred_mode, &aconnector->base.modes, head) {
 		/* Search for preferred mode */
 		if (preferred_mode->type & DRM_MODE_TYPE_PREFERRED) {