Merge pull request #1231 from Unity-Technologies/stacklit

Fix roughness transfer from bsdfdata to precalculated data.

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Material/StackLit/StackLit.hlsl

 
     float3 N = bsdfData.normalWS;
     preLightData.NdotV = dot(N, V);
+    preLightData.iblPerceptualRoughness[0] = bsdfData.perceptualRoughnessA;
+    preLightData.iblPerceptualRoughness[1] = bsdfData.perceptualRoughnessB;
 
     float NdotV = ClampNdotV(preLightData.NdotV);