[glib] Clarify g_type_init docs

[Matthias Clasen <matthiasc src gnome org>]

commit 26ecc52073285b4ee66da392e12b9a626116da7b
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Sep 23 11:13:57 2012 -0400

    Clarify g_type_init docs
    
    Mention that there's no way to undo it.
    https://bugzilla.gnome.org/show_bug.cgi?id=654239

 gobject/gtype.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)
---
diff --git a/gobject/gtype.c b/gobject/gtype.c
index 075e2bc..61c5cc9 100644
--- a/gobject/gtype.c
+++ b/gobject/gtype.c
@@ -4376,7 +4376,10 @@ g_type_init_with_debug_flags (GTypeDebugFlags debug_flags)
  * (such as the various fundamental type implementations or the signal
  * system).
  *
- * This function is idempotent.
+ * This function is idempotent: If you call it multiple times, all but
+ * the first calls will be silently ignored.
+ *
+ * There is no way to undo the effect of g_type_init().
  *
  * Since version 2.24 this also initializes the thread system
  */