Fix compile errors

Assets/ScriptableRenderLoop/HDRenderLoop/Sky/Resources/AtmosphericScattering.hlsl

 }
 
 float RayleighPhase(float cosTheta) {
-    const float f = 3.f / (16.f * M_PI);
+    const float f = 3.f / (16.f * PI);
-    const float f = 3.f / (8.f * M_PI);
+    const float f = 3.f / (8.f * PI);
     return f * HenyeyGreensteinPhase(anisotropy, cosTheta);
 }
 
         float4 mfWeights = float4(fWeights.z * fWeights.y, fWeights.x * fWeights.y, fWeights.x * fWeights.w, fWeights.z * fWeights.w);
         return dot(occ, mfWeights * maskDepth) / dot(mfWeights, maskDepth);
     }
+#endif //defined(ATMOSPHERICS_OCCLUSION_EDGE_FIXUP)
 #else //defined(ATMOSPHERICS_OCCLUSION)
     return 1.f;
 #endif //defined(ATMOSPHERICS_OCCLUSION)

Assets/ScriptableRenderLoop/HDRenderLoop/Sky/Resources/SkyHDRI.shader

             #pragma vertex Vert
             #pragma fragment Frag
 
+            #include "Color.hlsl"
-        
+            #include "Assets/ScriptableRenderLoop/HDRenderLoop/ShaderVariables.hlsl"
+            #include "AtmosphericScattering.hlsl"
+
             TEXTURECUBE(_Cubemap);
             SAMPLERCUBE(sampler_Cubemap);
             float4 _SkyParam; // x exposure, y multiplier, z rotation