message: Fixed few more issues in PSO create info validation
diff: namespace Diligent
  {
  -#define LOG_PSO_ERROR_AND_THROW(...) LOG_ERROR_AND_THROW("Description of ", GetPipelineTypeString(PSODesc.PipelineType), " PSO '", PSODesc.Name, "' is invalid: ", ##__VA_ARGS__)
  +#define LOG_PSO_ERROR_AND_THROW(...) LOG_ERROR_AND_THROW("Description of ", GetPipelineTypeString(PSODesc.PipelineType), " PSO '", (PSODesc.Name != nullptr ? PSODesc.Name : ""), "' is invalid: ", ##__VA_ARGS__)
  namespace
  {
  @@ -179,14 +179,14 @@ void ValidateGraphicsPipelineCreateInfo(const GraphicsPipelineStateCreateInfo& C
  if (PSODesc.PipelineType == PIPELINE_TYPE_GRAPHICS)
  {
  if (CreateInfo.pVS == nullptr)
  - LOG_ERROR_AND_THROW("Vertex shader must not be null.");
  + LOG_PSO_ERROR_AND_THROW("Vertex shader must not be null.");
  DEV_CHECK_ERR(CreateInfo.pAS == nullptr && CreateInfo.pMS == nullptr, "Mesh shaders are not supported in graphics pipeline.");
  }
  else if (PSODesc.PipelineType == PIPELINE_TYPE_MESH)
  {
  if (CreateInfo.pMS == nullptr)
  - LOG_ERROR_AND_THROW("Mesh shader must not be null.");
  + LOG_PSO_ERROR_AND_THROW("Mesh shader must not be null.");
  DEV_CHECK_ERR(CreateInfo.pVS == nullptr && CreateInfo.pGS == nullptr && CreateInfo.pDS == nullptr && CreateInfo.pHS == nullptr,
  "Vertex, geometry and tessellation shaders are not supported in a mesh pipeline.");
  