Attempt to better explain secure server creation

include/grpc/grpc.h

@@ -549,16 +549,11 @@ grpc_call_error grpc_server_request_call(
 grpc_server *grpc_server_create(grpc_completion_queue *cq,
                                 const grpc_channel_args *args);
 
-/* Add a http2 over tcp listener.
+/* Add a HTTP2 over plaintext over tcp listener.
    Returns bound port number on success, 0 on failure.
    REQUIRES: server not started */
 int grpc_server_add_http2_port(grpc_server *server, const char *addr);
 
-/* Add a secure port to server.
-   Returns bound port number on success, 0 on failure.
-   REQUIRES: server not started */
-int grpc_server_add_secure_http2_port(grpc_server *server, const char *addr);
-
 /* Start a server - tells all listeners to start listening */
 void grpc_server_start(grpc_server *server);
 

include/grpc/grpc_security.h

@@ -162,6 +162,13 @@ grpc_server *grpc_secure_server_create(grpc_server_credentials *creds,
                                        grpc_completion_queue *cq,
                                        const grpc_channel_args *args);
 
+/* Add a HTTP2 over an encrypted link over tcp listener.
+   Server must have been created with grpc_secure_server_create.
+   Returns bound port number on success, 0 on failure.
+   REQUIRES: server not started */
+int grpc_server_add_secure_http2_port(grpc_server *server, const char *addr);
+
+
 #ifdef __cplusplus
 }
 #endif