We had issues with people trying to build the 4.2.0 tarball while not having
automake-1.14 installed. This appears to be due to timestamp issues resulting
in autotools trying to regenerate various files and then the Makefiles deciding
they need specific versions of automake.
This can be fixed by adding AM_MAINTAINER_MODE([disable]) to configure.ac,
which means that any build will not try and rebuild any build scripts unless
explicitly requested.
Pacman developers can consider using --enable-maintainer-mode when running
configure to use autotools to update build scripts as needed.
Signed-off-by: Allan McRae