[simd] Disable Simd Scalar lowering for x64, enable tests for all other architectures.

test/cctest/wasm/wasm-run-utils.h

Index: test/cctest/wasm/wasm-run-utils.h
diff --git a/test/cctest/wasm/wasm-run-utils.h b/test/cctest/wasm/wasm-run-utils.h
index 284b21c7c45ab1e70fcb479862750cb4c0ffcd6b..eff411f2a6fd75cd7e10544e9d9ed9fae4aa1e1e 100644
--- a/test/cctest/wasm/wasm-run-utils.h
+++ b/test/cctest/wasm/wasm-run-utils.h
@@ -307,7 +307,9 @@ inline void TestBuildingGraph(Zone* zone, JSGraph* jsgraph, ModuleEnv* module,
     FATAL(str.str().c_str());
   }
   builder.Int64LoweringForTesting();
-  builder.SimdScalarLoweringForTesting();
+  if (!CpuFeatures::SupportsSimd128()) {
+    builder.SimdScalarLoweringForTesting();
+  }
 }
 
 template <typename ReturnType>