Remove redundant operations

Assets/ScriptableRenderLoop/HDRenderLoop/Material/Lit/Lit.hlsl

         float lightPdf = 0.0;               // Pdf of the light sample
 
         float2 u = Hammersley2d(i, sampleCount);
-        u = frac(u + randNum + 0.5);
+        u = frac(u + randNum);
 
         float4x4 localToWorld = float4x4(float4(lightData.right, 0.0), float4(lightData.up, 0.0), float4(lightData.forward, 0.0), float4(lightData.positionWS, 1.0));
 
     for (uint i = 0; i < sampleCount; ++i)
     {
         float2 u    = Hammersley2d(i, sampleCount);
-        u           = frac(u + randNum + 0.5);
+        u           = frac(u + randNum);
 
         float3 L;
         float NdotL;
     for (uint i = 0; i < sampleCount; ++i)
     {
         float2 u    = Hammersley2d(i, sampleCount);
-        u           = frac(u + randNum + 0.5);
+        u           = frac(u + randNum);
 
         float3 L;
         float NdotL;
     float    NdotV        = GetShiftedNdotV(N, V, false);
     float3   acc          = float3(0.0, 0.0, 0.0);
 
+
     // Add some jittering on Hammersley2d
     float2 randNum  = InitRandom(V.xy * 0.5 + 0.5);
 
-        u           = frac(u + randNum + 0.5);
+        u           = frac(u + randNum);
 
         float VdotH;
         float NdotL;

Assets/ScriptableRenderLoop/ShaderLibrary/ImageBasedLighting.hlsl

                         out float    NdotL)
 {
     // Cosine sampling - ref: http://www.rorydriscoll.com/2009/01/07/better-sampling/
-    float cosTheta = sqrt(saturate(1.0 - u.x));
+    float cosTheta = sqrt(1.0 - u.x);
     float sinTheta = sqrt(u.x);
     float phi      = TWO_PI * u.y;