GPU/HW: Support line drawing at >1x scale in D3D11 via GS

src/core/gpu_hw_shadergen.h

@@ -21,6 +21,7 @@ public:
   std::string GenerateBatchVertexShader(bool textured);
   std::string GenerateBatchFragmentShader(GPU_HW::BatchRenderMode transparency, GPU::TextureMode texture_mode,
                                           bool dithering);
+  std::string GenerateBatchLineExpandGeometryShader();
   std::string GenerateScreenQuadVertexShader();
   std::string GenerateFillFragmentShader();
   std::string GenerateCopyFragmentShader();