test of1.2: add test code of OFPErrorExperimenterMsg

- add test code of max and min to OFPErrorExperimenterMsg

Signed-off-by: KONDOH Tasuku <kondoh.tasuku@po.ntts.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>