ch7006: correctly handling failed allocation

Since drm_property_create_range can be failed in memory pressure,
it needs to be checked and return -ENOMEM.
Signed-off-by: NInsu Yun <wuninsu@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1454025276-13465-1-git-send-email-wuninsu@gmail.com

drivers/gpu/drm/i2c/ch7006_drv.c

@@ -253,6 +253,8 @@ static int ch7006_encoder_create_resources(struct drm_encoder *encoder,
 	drm_mode_create_tv_properties(dev, NUM_TV_NORMS, ch7006_tv_norm_names);
 
 	priv->scale_property = drm_property_create_range(dev, 0, "scale", 0, 2);
+	if (!priv->scale_property)
+		return -ENOMEM;
 
 	drm_object_attach_property(&connector->base, conf->tv_select_subconnector_property,
 				      priv->select_subconnector);