autotest: Make netperf2 cross compile

- Switch to configure wrapper function

TEST=Built for arm-generic and x86-generic
Bug=None

Review URL: http://codereview.chromium.org/1234001
diff --git a/client/tests/netperf2/netperf2.py b/client/tests/netperf2/netperf2.py
index 8a50b8f..28a3754 100644
--- a/client/tests/netperf2/netperf2.py
+++ b/client/tests/netperf2/netperf2.py
@@ -21,7 +21,7 @@
         # CPU_SET_S defined on /usr/include/sched.h, backported from
         # upstream svn trunk
         utils.system('patch -p0 < ../fix_netperf_build.patch')
-        utils.system('./configure')
+        utils.configure()
         utils.system('make')
         utils.system('sync')