Don't check certificate type against ciphersuite for TLS 1.3

Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2324)

ssl/statem/statem_clnt.c

@@ -1562,7 +1562,12 @@ MSG_PROCESS_RETURN tls_process_server_certificate(SSL *s, PACKET *pkt)
                SSL_R_UNKNOWN_CERTIFICATE_TYPE);
         goto f_err;
     }
-
+    /*
+     * Check certificate type is consistent with ciphersuite. For TLS 1.3
+     * skip check since TLS 1.3 ciphersuites can be used with any certificate
+     * type.
+     */
+    if (!SSL_IS_TLS13(s)) {
         exp_idx = ssl_cipher_get_cert_index(s->s3->tmp.new_cipher);
         if (exp_idx >= 0 && i != exp_idx
             && (exp_idx != SSL_PKEY_GOST_EC ||
@@ -1574,6 +1579,7 @@ MSG_PROCESS_RETURN tls_process_server_certificate(SSL *s, PACKET *pkt)
                    SSL_R_WRONG_CERTIFICATE_TYPE);
             goto f_err;
         }
+    }
     s->session->peer_type = i;
 
     X509_free(s->session->peer);