Fix runtest build step.

Update make syntax to new 'mmm' logic.

Bug 4556556

Change-Id: Ie1fd5f6714ee7ef731b063751e0ddd674bc31021
diff --git a/testrunner/runtest.py b/testrunner/runtest.py
index 3ecc77b..f7d72af 100755
--- a/testrunner/runtest.py
+++ b/testrunner/runtest.py
@@ -264,7 +264,7 @@
 
       # mmm cannot be used from python, so perform a similar operation using
       # ONE_SHOT_MAKEFILE
-      cmd = 'ONE_SHOT_MAKEFILE="%s" make -j%s -C "%s" files %s' % (
+      cmd = 'ONE_SHOT_MAKEFILE="%s" make -j%s -C "%s" all_modules %s' % (
           target_build_string, self._options.make_jobs, self._root_path,
           extra_args_string)
       logger.Log(cmd)