We use PY_LOG_COMPILER in Makefile.am for running *.py tests, which requires
automake's parallel test runner. This has only been the default from 1.13 on.
As we only require automake 1.11, add it as an option explicitly.
AC_SYS_LARGEFILE
AC_PREFIX_DEFAULT([/usr])
AM_MAINTAINER_MODE([enable])
-AM_INIT_AUTOMAKE([foreign 1.11 -Wall -Wno-portability silent-rules tar-pax no-dist-gzip dist-xz subdir-objects])
+AM_INIT_AUTOMAKE([foreign 1.11 -Wall -Wno-portability silent-rules tar-pax no-dist-gzip dist-xz subdir-objects parallel-tests])
AM_SILENT_RULES([yes])
AC_CANONICAL_HOST
AC_DEFINE_UNQUOTED([CANONICAL_HOST], "$host", [Canonical host string.])