server: set tcp port and bind address before init

server: set tcp port and bind address before init

All the servers open the listening socket during openocd "init";
it's not possible to change the tcp port or the bind address
after "init".

In current code, the call order during "init" permits to change
the port and bind address of tcl and telnet server if the related
command is issued after "init" in the same script or on openocd
command line. This is not guaranteed to work if the call order
during "init" changes, so it's incorrect.

Change the commands "bindto" and "*_port" to COMMAND_CONFIG.

Change-Id: Id88f225a67a872b4bcaf3b799466bddedc248015
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reported-by: Christopher Head <chead@zaber.com>
Fixes: https://sourceforge.net/p/openocd/tickets/264/
Reviewed-on: http://openocd.zylin.com/5595
Reviewed-by: Christopher Head <chead@zaber.com>
Tested-by: jenkins