drm/bridge/analogix/anx78xx: Setup encoder before registering connector

Since encoder mappings for connectors are exposed to userspace, we should
be attaching the encoder before exposing the connector to userspace. Just a
drive-by fix for an issue I noticed while fixing up usages of
drm_dp_aux_init()/drm_dp_aux_register() across the tree.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210219215326.2227596-9-lyude@redhat.com

drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c

@@ -924,12 +924,6 @@ static int anx78xx_bridge_attach(struct drm_bridge *bridge,
 	drm_connector_helper_add(&anx78xx->connector,
 				 &anx78xx_connector_helper_funcs);
 
-	err = drm_connector_register(&anx78xx->connector);
-	if (err) {
-		DRM_ERROR("Failed to register connector: %d\n", err);
-		return err;
-	}
-
 	anx78xx->connector.polled = DRM_CONNECTOR_POLL_HPD;
 
 	err = drm_connector_attach_encoder(&anx78xx->connector,
@@ -939,6 +933,12 @@ static int anx78xx_bridge_attach(struct drm_bridge *bridge,
 		return err;
 	}
 
+	err = drm_connector_register(&anx78xx->connector);
+	if (err) {
+		DRM_ERROR("Failed to register connector: %d\n", err);
+		return err;
+	}
+
 	return 0;
 }