Include session record from header file instead of duplicating it

include/ejabberd_sm.hrl

@@ -1,3 +1,6 @@
+-ifndef(EJABBERD_SM_HRL).
+-define(EJABBERD_SM_HRL, true).
+
 -record(session, {sid, usr, us, priority, info}).
 -record(session_counter, {vhost, count}).
 -type sid() :: {erlang:timestamp(), pid()}.
@@ -5,3 +8,5 @@
 -type info() :: [{conn, atom()} | {ip, ip()} | {node, atom()}
                  | {oor, boolean()} | {auth_module, atom()}].
 -type prio() :: undefined | integer().
+
+-endif.

src/mod_admin_extra.erl

@@ -89,15 +89,13 @@
 	 stats/1, stats/2
 	]).
 
+
 -include("ejabberd.hrl").
 -include("ejabberd_commands.hrl").
 -include("mod_roster.hrl").
+-include("ejabberd_sm.hrl").
 -include("jlib.hrl").
 
-%% Copied from ejabberd_sm.erl
--record(session, {sid, usr, us, priority, info}).
-
-
 %%%
 %%% gen_mod
 %%%