Further speed up examples for testing

BUG=aomedia:2645

Change-Id: I725d65962800fe6645c2b8bc075dd198fc4621d2
diff --git a/test/tools_common.sh b/test/tools_common.sh
index c087106..d40709b 100755
--- a/test/tools_common.sh
+++ b/test/tools_common.sh
@@ -196,7 +196,7 @@
 
 # Echoes "fast" encode params for use with aomenc.
 aomenc_encode_test_fast_params() {
-  echo "--cpu-used=1
+  echo "--cpu-used=2
         --limit=${AV1_ENCODE_TEST_FRAME_LIMIT}
         --lag-in-frames=0
         --test-decode=fatal"