mbedtls_cmac_self_test() function

\c 0 on success. \c 1 on failure.

In case the CMAC routines are provided by an alternative implementation (i.e. #MBEDTLS_CMAC_ALT is defined), the checkup routine will succeed even if the implementation does not support the less widely used AES-192 or 3DES primitives. The self-test requires at least AES-128 and AES-256 to be supported by the underlying implementation.