HDRenderPipeline: Fix bug with compo mask in layered material

Assets/ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/LitData.hlsl

 #endif
 
 #if defined(_MAIN_LAYER_INFLUENCE_MODE)
-    surfaceData.baseColor = ComputeMainBaseColorInfluence(surfaceData0.baseColor, surfaceData1.baseColor, surfaceData2.baseColor, surfaceData3.baseColor, alpha, layerTexCoord, weights);
+    surfaceData.baseColor = ComputeMainBaseColorInfluence(surfaceData0.baseColor, surfaceData1.baseColor, surfaceData2.baseColor, surfaceData3.baseColor, alpha0, layerTexCoord, weights);
     float3 normalTS = ComputeMainNormalInfluence(input, normalTS0, normalTS1, normalTS2, normalTS3, layerTexCoord, weights);
 #else
     surfaceData.baseColor = SURFACEDATA_BLEND_VECTOR3(surfaceData, baseColor, weights);