Without this patch, rebar fails to find include file fxml.hrl.

Signed-off-by: Christophe Romain <cromain@process-one.net>

diff --git a/include/xmpp.hrl b/include/xmpp.hrl
index afa5f61..678858e 100644
--- a/include/xmpp.hrl
+++ b/include/xmpp.hrl
@@ -26,7 +26,7 @@
 -include("ns.hrl").
 -include("jid.hrl").
 -include("xmpp_codec.hrl").
--include("fxml.hrl").
+-include_lib("p1_xml/include/fxml.hrl").

 -type stanza() :: iq() | presence() | message().