configure: Clarify the description of --disable-module-dirauth

Part of 32123.

configure.ac

@@ -258,7 +258,7 @@ m4_define(MODULES, dirauth)
 dnl Directory Authority module.
 AC_ARG_ENABLE([module-dirauth],
               AS_HELP_STRING([--disable-module-dirauth],
-                             [Build tor without the Directory Authority module: tor can not run as an authority]),
+                             [Build tor without the Directory Authority module: tor can not run as a directory authority or bridge authority]),
               [], dnl Action if-given
               AC_DEFINE([HAVE_MODULE_DIRAUTH], [1],
                         [Compile with Directory Authority feature support]))