re-enable CDO options for CDI for test generation

m4/acx_options.m4

 AC_DEFUN([ACX_CDI_OPTIONS],
 [
 #  ----------------------------------------------------------------------
+#  Checks for multithreaded compiling + linking
+AC_ARG_WITH([threads],
+            [AC_HELP_STRING([--with-threads=<yes/no/directory>],
+                            [Compile + link for multithreading [default=yes]])],
+            [],
+            [with_threads=yes])
+THREADS_INCLUDE=''
+THREADS_LIBS=''
+AS_CASE([$with_threads],
+        [no],[AC_MSG_CHECKING([multithreading])
+              AC_MSG_RESULT([suppressed])],
+        [yes],[AX_PTHREAD([AC_DEFINE([HAVE_LIBPTHREAD],[1],[Define 1 for multithread support])],[AC_MSG_ERROR([multithreaded settings NOT found])])
+               LIBS="$PTHREAD_LIBS $LIBS"
+               CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+               CC="$PTHREAD_CC"
+               AS_ECHO(["CC:$CC CFLAGS:$CFLAGS LIBS:$LIBS"])],
+        [*],[THREADS_ROOT=$with_threads
+             LDFLAGS="-L$THREADS_ROOT/lib $LDFLAGS"
+             CPPFLAGS="-I$THREADS_ROOT/include $CPPFLAGS "
+             AC_CHECK_HEADERS(pthread.h)
+             AC_CHECK_LIB([pthread],[pthread_create])
+             THREADS_LIBS=" -L$THREADS_ROOT/lib -lpthread"
+             THREADS_INCLUDE=" -I$THREADS_ROOT/include"])
+AC_SUBST([THREADS_INCLUDE])
+AC_SUBST([THREADS_LIBS])
+#  ----------------------------------------------------------------------
 #  Compile application with SZLIB library, needed for GRIB1
 SZLIB_INCLUDE=''
 SZLIB_LIBS=''