of12: set ActionOutput default max_len to zero

same as of10.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
of13: set ActionOutput default max_len to zero

same as of10.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
add simple learning switch app for OF1.3

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
add simple learning switch app for OF1.2

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>