[gnome-multi-writer] trivial: Don't unref NULL if libusb fails to load

[Richard Hughes <rhughes src gnome org>]

commit 11a2521648a2c8299fddc9a1e29dd9caff8e4ce6
Author: Richard Hughes <richard hughsie com>
Date:   Fri Jan 9 14:29:24 2015 +0000

    trivial: Don't unref NULL if libusb fails to load

 src/gmw-main.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/src/gmw-main.c b/src/gmw-main.c
index 92ddb24..1e8f5bb 100644
--- a/src/gmw-main.c
+++ b/src/gmw-main.c
@@ -1609,7 +1609,8 @@ out:
                        g_object_unref (priv->image_file);
                if (priv->cancellable != NULL)
                        g_object_unref (priv->cancellable);
-               g_object_unref (priv->application);
+               if (priv->application != NULL)
+                       g_object_unref (priv->application);
                g_thread_pool_free (priv->thread_pool, TRUE, TRUE);
                g_mutex_clear (&priv->thread_pool_mutex);
                g_mutex_clear (&priv->devices_mutex);