winks: Give the ksvideosrc PRIMARY rank

It's the primary video source on Windows, so give it a
rank for autoplugging by camerabin and friends
diff --git a/sys/winks/gstksvideosrc.c b/sys/winks/gstksvideosrc.c
index c2bad34..98f0b4c 100644
--- a/sys/winks/gstksvideosrc.c
+++ b/sys/winks/gstksvideosrc.c
@@ -1013,7 +1013,7 @@
       0, "Kernel streaming video source");
 
   if (!gst_element_register (plugin, "ksvideosrc",
-          GST_RANK_NONE, GST_TYPE_KS_VIDEO_SRC))
+          GST_RANK_PRIMARY, GST_TYPE_KS_VIDEO_SRC))
     return FALSE;
 
   if (!gst_device_provider_register (plugin, "ksdeviceprovider",