HDRenderPipeline: Revert minor code done by decals PR that should have been reverted also

ScriptableRenderPipeline/HDRenderPipeline/HDRP/ShaderPass/VertMesh.hlsl

     float3 normalWS = float3(0.0, 0.0, 0.0); // We need this case to be able to compile ApplyVertexModification that doesn't use normal.
 #endif
 
-	float4 tangentWS = float4(0.0, 0.0, 0.0, 0.0);
-    tangentWS = float4(TransformObjectToWorldDir(input.tangentOS.xyz), input.tangentOS.w);
+     float4 tangentWS = float4(TransformObjectToWorldDir(input.tangentOS.xyz), input.tangentOS.w);
 #endif
 
     // TODO: deal with camera center rendering and instancing (This is the reason why we always perform two  steps transform to clip space + instancing matrix)