Add TLS_ECDHE_ECDSA_WITH_AES_128_CCM_8 to the list for use with x509
certificates. The LWM2M v1.1 specification says that a LWM2M client
which used X509 certificates must support this ciphersuite and
additional ciphersuites may be supported.
Signed-off-by: Jeroen Broersen <jbroersen@interact.nl>