[gnome-control-center] info: Fix leak when /etc/os-release not found

[Robert Ancell <rancell src gnome org>]

commit c3d33581304ad0df6c9c222600fe2ba8233cd33f
Author: Robert Ancell <robert ancell canonical com>
Date:   Wed Aug 21 17:26:49 2019 +1200

    info: Fix leak when /etc/os-release not found
    
    There is a missing return statement, this was broken in 331f0d1

 panels/info/cc-info-overview-panel.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/panels/info/cc-info-overview-panel.c b/panels/info/cc-info-overview-panel.c
index 0d0a17fcf..7fce8691e 100644
--- a/panels/info/cc-info-overview-panel.c
+++ b/panels/info/cc-info-overview-panel.c
@@ -437,7 +437,7 @@ get_os_name (void)
   os_info = get_os_info ();
 
   if (!os_info)
-    g_strdup (_("Unknown"));
+    return g_strdup (_("Unknown"));
 
   name = g_hash_table_lookup (os_info, "NAME");
   version_id = g_hash_table_lookup (os_info, "VERSION_ID");