Shorten test time of AVxEncoderThreadLSTestLarge

This commit reduces the number of cpu-used values used in the test to
reduce test time.

Change-Id: Ibb1e26f2ace1f765ed8dbec468de49831ee777db
diff --git a/test/ethread_test.cc b/test/ethread_test.cc
index 674b61a..20f4b5a 100644
--- a/test/ethread_test.cc
+++ b/test/ethread_test.cc
@@ -495,6 +495,6 @@
 AV1_INSTANTIATE_TEST_CASE(AVxEncoderThreadLSTestLarge,
                           ::testing::Values(::libaom_test::kTwoPassGood,
                                             ::libaom_test::kOnePassGood),
-                          ::testing::Range(0, 4), ::testing::Values(0, 6),
-                          ::testing::Values(0, 6), ::testing::Values(0, 1));
+                          ::testing::Values(1, 3), ::testing::Values(0, 6),
+                          ::testing::Values(0, 6), ::testing::Values(1));
 }  // namespace