message: Fixed uninitialized local variable
  This patch solves the following Visual C compiler error when attempting to build the "util/tests/demos.sln" VS project from the command-line w/ MSBUILD:
  `error C2220: the following warning is treated as an error
  warning C4701: potentially uninitialized local variable 'xfbpipe' used`
diff: @@ -336,7 +336,7 @@ void main()
  VkPipeline stride0pipe = createGraphicsPipeline(pipeCreateInfo);
  - VkPipeline xfbpipe;
  + VkPipeline xfbpipe = NULL;
  VkPipelineRasterizationStateStreamCreateInfoEXT rastInfo = {
  VK_STRUCTURE_TYPE_PIPELINE_RASTERIZATION_STATE_STREAM_CREATE_INFO_EXT, NULL, 0, 2,
  