compositor-drm: Fix memory leak in update_outputs

We need to correctly free every connector we retrieve. We currently loose them
if they are not connected.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
diff --git a/compositor/compositor-drm.c b/compositor/compositor-drm.c
index 855a811..9f76187 100644
--- a/compositor/compositor-drm.c
+++ b/compositor/compositor-drm.c
@@ -609,10 +609,14 @@
 		int connector_id = resources->connectors[i];
 
 		connector = drmModeGetConnector(ec->drm.fd, connector_id);
-		if (connector == NULL ||
-		    connector->connection != DRM_MODE_CONNECTED)
+		if (connector == NULL)
 			continue;
 
+		if (connector->connection != DRM_MODE_CONNECTED) {
+			drmModeFreeConnector(connector);
+			continue;
+		}
+
 		connected |= (1 << connector_id);
 
 		if (!(ec->connector_allocator & (1 << connector_id))) {