tests: Fix VKTriangleTest to set the usage flags correctly on buffer.

By default, you get transfer_src|transfer_dst.

Signed-off-by: Chris Forbes <chrisforbes@google.com>
diff --git a/tests/layer_validation_tests.cpp b/tests/layer_validation_tests.cpp
index eff0166..341f557 100644
--- a/tests/layer_validation_tests.cpp
+++ b/tests/layer_validation_tests.cpp
@@ -383,7 +383,8 @@
 
     ASSERT_NO_FATAL_FAILURE(InitViewport());
 
-    VkConstantBufferObj constantBuffer(m_device, bufSize * 2, sizeof(float), (const void *)&data);
+    VkConstantBufferObj constantBuffer(m_device, bufSize * 2, sizeof(float), (const void *)&data,
+                                       VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT);
 
     VkShaderObj vs(m_device, vertShaderText, VK_SHADER_STAGE_VERTEX_BIT, this);
     VkShaderObj ps(m_device, fragShaderText, VK_SHADER_STAGE_FRAGMENT_BIT, this);