[gnome-builder] plugins: sysroot: fix warning uninitialized g_autofree variable

[Christian Hergert <chergert src gnome org>]

commit 48bf0fe097b76291a472da8076358ac797f6448b
Author: Daniel Buch <boogiewasthere gmail com>
Date:   Thu Nov 8 13:19:04 2018 +0100

    plugins: sysroot: fix warning uninitialized g_autofree variable

 src/plugins/sysroot/gbp-sysroot-preferences-addin.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/plugins/sysroot/gbp-sysroot-preferences-addin.c 
b/src/plugins/sysroot/gbp-sysroot-preferences-addin.c
index 607340ab4..bce87b950 100644
--- a/src/plugins/sysroot/gbp-sysroot-preferences-addin.c
+++ b/src/plugins/sysroot/gbp-sysroot-preferences-addin.c
@@ -39,7 +39,7 @@ sysroot_preferences_add_new (GbpSysrootPreferencesAddin *self,
 {
   GtkWidget *pref_row = NULL;
   guint id = 0;
-  g_autofree gchar *new_target;
+  g_autofree gchar *new_target = NULL;
   GbpSysrootManager *sysroot_manager = NULL;
 
   g_assert (GBP_IS_SYSROOT_PREFERENCES_ADDIN (self));