ecore_drm2: Fix a condition where no outputs are enabled

If the first output we test is disconnected but has the crtc of
the primary display assigned then we'll fail to assign the crtc
to the connector it's really connected to later.

This is a quick hack as trying to sort this out properly may be
too invasive for the upcoming 1.18 and isn't really important until
1.19 supports multihead anyway.

src/lib/ecore_drm2/ecore_drm2_outputs.c

@@ -234,6 +234,15 @@ _output_crtc_find(const drmModeRes *res, const drmModeConnector *conn, Ecore_Drm
    uint32_t crtc;
    int i = 0, j = 0;
 
+   /* Skip all disconnected connectors...
+    *
+    * When a connector is disconnected it still has an encoder id
+    * which messes up our output selection code later.  When we support
+    * multi-head properly and hotplug becomes a real thing we'll
+    * need to revisit this hack (and the crtc assignment code as well)
+    */
+   if (conn->connection != DRM_MODE_CONNECTED) return -1;
+
    for (j = 0; j < conn->count_encoders; j++)
      {
         enc = drmModeGetEncoder(dev->fd, conn->encoders[j]);