Patch by ILEoo to make the telnet interface work with "telnet" again (on...

Patch by ILEoo to make the telnet interface work with "telnet" again (on linux). Looks ok according to the recv(2) manpage. Please fix if this is flawed.

modules/control/telnet.c

@@ -379,7 +379,7 @@ static void Run( intf_thread_t *p_intf )
                                    cl->i_mode + 2 );
                 }
 
-                if( i_recv <= 0 )
+                if( i_recv == 0  || ( i_recv == -1 &&  errno != EAGAIN && errno != 0 ) )
                 {
                     net_Close( cl->fd );
                     TAB_REMOVE( p_intf->p_sys->i_clients ,