crypto: testmgr - expand twofish test vectors

The AVX implementation of the twofish cipher processes 8 blocks parallel, so we
need to make test vectors larger to check parallel code paths. Test vectors are
also large enough to deal with 16 block parallel implementations which may occur
in the future.

Signed-off-by: Johannes Goetzfried <[email protected]>
Signed-off-by: Jussi Kivilinna <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>