/* In OpenSSL, cipher components are separated by hyphens. In GnuTLS, they
were historically separated by underscores. So that I can use either form in my
tests, and also for general convenience, we turn underscores into hyphens here.
+
+XXX SSL_CTX_set_cipher_list() is replaced by SSL_CTX_set_ciphersuites()
+for TLS 1.3 . Since we do not call it at present we get the default list:
+TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256
*/
if (expciphers)