[gnome-software] trivial: Fix a warning when compiling with buildtype=debugoptimized

[Richard Hughes <rhughes src gnome org>]

commit 3dde2666b1dfe80f058ee831bb6d76fc4f395171
Author: Richard Hughes <richard hughsie com>
Date:   Mon Jul 10 16:32:18 2017 +0100

    trivial: Fix a warning when compiling with buildtype=debugoptimized

 src/gs-updates-page.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/gs-updates-page.c b/src/gs-updates-page.c
index 9eb503a..6e7374a 100644
--- a/src/gs-updates-page.c
+++ b/src/gs-updates-page.c
@@ -1486,7 +1486,7 @@ upgrade_reboot_failed_cb (GObject *source,
        GsUpdatesPage *self = (GsUpdatesPage *) user_data;
        GsApp *app;
        g_autoptr(GError) error = NULL;
-       g_autoptr(GsPluginJob) plugin_job;
+       g_autoptr(GsPluginJob) plugin_job = NULL;
        g_autoptr(GVariant) retval = NULL;
 
        /* get result */