[ekiga/v4_0] HACKING: Fix typo error by changing 'o' to 'a'

[Eugen Dedu <ededu src gnome org>]

commit cad94cf7412f6ad375a754cf81c9c5262cac8086
Author: Michael Dorrington <michael dorrington gmail com>
Date:   Thu Jan 3 00:24:20 2013 +0100

    HACKING: Fix typo error by changing 'o' to 'a'

 HACKING |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/HACKING b/HACKING
index 7171f26..876c749 100644
--- a/HACKING
+++ b/HACKING
@@ -26,5 +26,5 @@ Developers:
 - Encoding: Ekiga is completely UTF-8.  The only exception is that the
   (audio/video) device names are in system codepage for Windows.  The
   latin2utf and utf2latin functions take care of that.
-- To find out which callbacks are called when o value in gconf
+- To find out which callbacks are called when a value in gconf
   changes, search gm_conf_notifier_add in ekiga code.