drm/radeon/kms: fix typo in legacy internal tmds mode fixup

Call to set active device was missing.

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon_legacy_encoders.c b/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
index 2670a9e..a1d9d29 100644
--- a/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
+++ b/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
@@ -427,7 +427,8 @@
 					      struct drm_display_mode *mode,
 					      struct drm_display_mode *adjusted_mode)
 {
-
+	/* set the active encoder to connector routing */
+	radeon_encoder_set_active_device(encoder);
 	drm_mode_set_crtcinfo(adjusted_mode, 0);
 
 	return true;