xdata/xodtemplate: wrong processing for deprecated service extinfo

parameters for function xodtemplate_create_service_list() function
are in the wrong order. fixing the parameters order, function works
correctly but nagios segfaults after retrieve list due to cumulative
elements on master_servicelist variable.

making master_servicelist equal to NULL makes nagios works correctly.

Signed-off-by: Ricardo Maraschini <ricardo.maraschini@gmail.com>