HDRenderPipeline: Removed unused directionalShadowSplitSphereSqr

ScriptableRenderPipeline/HDRenderPipeline/HDRP/HDStringConstants.cs

         public static readonly int _EnvLightDatas = Shader.PropertyToID("_EnvLightDatas");
         public static readonly int _EnvLightCount = Shader.PropertyToID("_EnvLightCount");
         public static readonly int _ShadowDatas = Shader.PropertyToID("_ShadowDatas");
-        public static readonly int _DirShadowSplitSpheres = Shader.PropertyToID("_DirShadowSplitSpheres");
         public static readonly int _NumTileFtplX = Shader.PropertyToID("_NumTileFtplX");
         public static readonly int _NumTileFtplY = Shader.PropertyToID("_NumTileFtplY");
         public static readonly int _NumTileClusteredX = Shader.PropertyToID("_NumTileClusteredX");

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Lighting/LightLoop/LightLoop.cs

             public List<LightData> lights;
             public List<EnvLightData> envLights;
             public List<ShadowData> shadows;
-            public Vector4[] directionalShadowSplitSphereSqr;
 
             public List<SFiniteLightBound> bounds;
             public List<LightVolumeData> lightVolumes;
                 lights = new List<LightData>();
                 envLights = new List<EnvLightData>();
                 shadows = new List<ShadowData>();
-                directionalShadowSplitSphereSqr = new Vector4[k_MaxCascadeCount];
 
                 bounds = new List<SFiniteLightBound>();
                 lightVolumes = new List<LightVolumeData>();
                 cmd.SetGlobalBuffer(HDShaderIDs._EnvLightDatas, s_EnvLightDatas);
                 cmd.SetGlobalInt(HDShaderIDs._EnvLightCount, m_lightList.envLights.Count);
                 cmd.SetGlobalBuffer(HDShaderIDs._ShadowDatas, s_shadowDatas);
-                cmd.SetGlobalVectorArray(HDShaderIDs._DirShadowSplitSpheres, m_lightList.directionalShadowSplitSphereSqr);
 
                 cmd.SetGlobalInt(HDShaderIDs._NumTileFtplX, GetNumTileFtplX(camera));
                 cmd.SetGlobalInt(HDShaderIDs._NumTileFtplY, GetNumTileFtplY(camera));