tests: fix some AES-CCM tests

In TLS, the AES-CCM test is commented out because CCM is not supported
by cryptography. But the combined_modes_ccm keyword is made to skip
these tests.

In IPsec, some IPv4 tests are located in the IPv6 section. Also add the
same combination of test for the AES-CCM as the other modes.

Also, there is some errors in the key material as the *MUST*
implementation uses a 16 bytes key and a 3 bytes nonce. Fix those
lengths.

Signed-off-by: Thomas Faivre <thomas.faivre@6wind.com>