tcptls: use TLS_client_method with OpenSSL 1.1

OpenSSL 1.1 introduced TLS_client_method() and deprecated the previous
version-specific methods (such as TLSv1_client_method(). Other than
being simpler to use and more correct (gain support for TLS newer that
TLS1, in our case), the older ones produce a deprecation warning that
fails the build in dev-mode.

Change-Id: I257b1c8afd09dcb0d96cda3a41cb9f7a15d0ba07

main/tcptls.c

@@ -324,12 +324,16 @@ static int __ssl_setup(struct ast_tls_config *cfg, int client)
 			cfg->ssl_ctx = SSL_CTX_new(SSLv3_client_method());
 		} else
 #endif
+#if defined(OPENSSL_VERSION_NUMBER) && (OPENSSL_VERSION_NUMBER  >= 0x10100000L)
+		cfg->ssl_ctx = SSL_CTX_new(TLS_client_method());
+#else
 		if (ast_test_flag(&cfg->flags, AST_SSL_TLSV1_CLIENT)) {
 			cfg->ssl_ctx = SSL_CTX_new(TLSv1_client_method());
 		} else {
 			disable_ssl = 1;
 			cfg->ssl_ctx = SSL_CTX_new(SSLv23_client_method());
 		}
+#endif
 	} else {
 		disable_ssl = 1;
 		cfg->ssl_ctx = SSL_CTX_new(SSLv23_server_method());