Revert "disp: msm: dp: use the correct checksum for EDID"

This reverts commit eaed3221fa
which uses a downstream implementation for checksum calculation.
This will be fixed once the upstream changes to address checksum
calculation are merged.

Change-Id: I7a6ed1c4d4baf52533485d59bcdcb6dd1009d626
Signed-off-by: Tatenda Chipeperekwa <tatendac@codeaurora.org>

msm/dp/dp_panel.c

@@ -1969,12 +1969,7 @@ static void dp_panel_handle_sink_request(struct dp_panel *dp_panel)
 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
 
 	if (panel->link->sink_request & DP_TEST_LINK_EDID_READ) {
-		u8 checksum;
-
-		if (dp_panel->edid_ctrl->edid)
-			checksum = sde_get_edid_checksum(dp_panel->edid_ctrl);
-		else
-			checksum = dp_panel->connector->checksum;
+		u8 checksum = sde_get_edid_checksum(dp_panel->edid_ctrl);
 
 		panel->link->send_edid_checksum(panel->link, checksum);
 		panel->link->send_test_response(panel->link);