tests: Fix VkLayerTest.BufferMemoryNotBound

Wrong usage flags.

Signed-off-by: Chris Forbes <chrisforbes@google.com>
diff --git a/tests/layer_validation_tests.cpp b/tests/layer_validation_tests.cpp
index 017c81a..e1c1346 100644
--- a/tests/layer_validation_tests.cpp
+++ b/tests/layer_validation_tests.cpp
@@ -6945,7 +6945,7 @@
 
     VkBufferCreateInfo buf_info = {};
     buf_info.sType = VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO;
-    buf_info.usage = VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT;
+    buf_info.usage = VK_BUFFER_USAGE_TRANSFER_SRC_BIT;
     buf_info.size = 256;
     buf_info.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
     VkResult err = vkCreateBuffer(m_device->device(), &buf_info, NULL, &buffer);