HDRenderPipeline: Update also litTessellation.shader

Assets/ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/LitTessellation.shader

         [HideInInspector] _UVMappingMask("_UVMappingMask", Color) = (1, 0, 0, 0)
         [Enum(TangentSpace, 0, ObjectSpace, 1)] _NormalMapSpace("NormalMap space", Float) = 0
 
-        [Enum(Subsurface Scattering, 0, Standard, 1, Specular Color, 2)] _MaterialID("MaterialId", Int) = 1 // MaterialId.LitStandard
+        // Note: 2 and 3 are currently unused
+        [Enum(Subsurface Scattering, 0, Standard, 1, Anisotropy, 4, Specular Color, 5)] _MaterialID("MaterialId", Int) = 1 // MaterialId.RegularLighting
 
         [ToggleOff]  _EnablePerPixelDisplacement("Enable per pixel displacement", Float) = 0.0
         _PPDMinSamples("Min sample for POM", Range(1.0, 64.0)) = 5
     #pragma shader_feature _THICKNESSMAP
     #pragma shader_feature _SPECULARCOLORMAP
     #pragma shader_feature _VERTEX_WIND
+
+    // MaterialId are used as shader feature to allow compiler to optimize properly
+    // Note _MATID_STANDARD is not define as there is always the default case "_". We assign default as _MATID_STANDARD, so we never test _MATID_STANDARD
+    #pragma shader_feature _ _MATID_SSS _MATID_ANISO _MATID_SPECULAR
 
     #pragma multi_compile LIGHTMAP_OFF LIGHTMAP_ON
     #pragma multi_compile DIRLIGHTMAP_OFF DIRLIGHTMAP_COMBINED