Re-introduce none case for double sided

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Editor/Material/Lit/BaseLitUI.cs

         public enum DoubleSidedNormalMode
         {
             Flip,
-            Mirror
+            Mirror,
+            None
         }
 
         public enum TessellationMode
 
                     case DoubleSidedNormalMode.Flip: // Flip mode (in tangent space)
                         material.SetVector("_DoubleSidedConstants", new Vector4(-1.0f, -1.0f, -1.0f, 0.0f));
+                        break;
+
+                    case DoubleSidedNormalMode.None: // None mode (in tangent space)
+                        material.SetVector("_DoubleSidedConstants", new Vector4(1.0f, 1.0f, 1.0f, 0.0f));
                         break;
                 }
             }

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Material/LayeredLit/LayeredLit.shader

         [ToggleUI] _EnableBlendModePreserveSpecularLighting("Enable Blend Mode Preserve Specular Lighting", Float) = 1.0
 
         [ToggleUI] _DoubleSidedEnable("Double sided enable", Float) = 0.0
-        [Enum(Flip, 0, Mirror, 1)] _DoubleSidedNormalMode("Double sided normal mode", Float) = 1
+        [Enum(Flip, 0, Mirror, 1, None 2)] _DoubleSidedNormalMode("Double sided normal mode", Float) = 1
         [HideInInspector] _DoubleSidedConstants("_DoubleSidedConstants", Vector) = (1, 1, -1, 0)
 
         // For layering, due to combinatorial explosion, we only support SSS/Transmission and Standard. We let other case for the shader graph

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Material/LayeredLit/LayeredLitTessellation.shader

         [ToggleUI] _EnableBlendModePreserveSpecularLighting("Enable Blend Mode Preserve Specular Lighting", Float) = 1.0
 
         [ToggleUI] _DoubleSidedEnable("Double sided enable", Float) = 0.0
-        [Enum(Flip, 0, Mirror, 1)] _DoubleSidedNormalMode("Double sided normal mode", Float) = 1
+        [Enum(Flip, 0, Mirror, 1, None 2)] _DoubleSidedNormalMode("Double sided normal mode", Float) = 1
         [HideInInspector] _DoubleSidedConstants("_DoubleSidedConstants", Vector) = (1, 1, -1, 0)
 
         // For layering, due to combinatorial explosion, we only support SSS/Transmission and Standard. We let other case for the shader graph

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Material/Lit/Lit.shader

         [ToggleUI] _EnableBlendModePreserveSpecularLighting("Enable Blend Mode Preserve Specular Lighting", Float) = 1.0
 
         [ToggleUI] _DoubleSidedEnable("Double sided enable", Float) = 0.0
-        [Enum(Flip, 0, Mirror, 1)] _DoubleSidedNormalMode("Double sided normal mode", Float) = 1
+        [Enum(Flip, 0, Mirror, 1, None 2)] _DoubleSidedNormalMode("Double sided normal mode", Float) = 1
         [HideInInspector] _DoubleSidedConstants("_DoubleSidedConstants", Vector) = (1, 1, -1, 0)
 
         [Enum(UV0, 0, UV1, 1, UV2, 2, UV3, 3, Planar, 4, Triplanar, 5)] _UVBase("UV Set for base", Float) = 0

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Material/Lit/LitTessellation.shader

         [ToggleUI] _EnableBlendModePreserveSpecularLighting("Enable Blend Mode Preserve Specular Lighting", Float) = 1.0
 
         [ToggleUI] _DoubleSidedEnable("Double sided enable", Float) = 0.0
-        [Enum(Flip, 0, Mirror, 1)] _DoubleSidedNormalMode("Double sided normal mode", Float) = 1
+        [Enum(Flip, 0, Mirror, 1, None 2)] _DoubleSidedNormalMode("Double sided normal mode", Float) = 1
         [HideInInspector] _DoubleSidedConstants("_DoubleSidedConstants", Vector) = (1, 1, -1, 0)
 
         [Enum(UV0, 0, UV1, 1, UV2, 2, UV3, 3, Planar, 4, Triplanar, 5)] _UVBase("UV Set for base", Float) = 0

Tests/GraphicsTests/RenderPipeline/HDRenderPipeline/Scenes/1xxx_Materials/1202_Lit_DoubleSideNormalMode/DoubleSideNormalTest.mat

   stringTagMap: {}
   disabledShaderPasses:
   - DistortionVectors
+  - TransparentBackfaceDebugDisplay
-  - TransparentBackfaceDebugDisplay
   - MOTIONVECTORS
   m_SavedProperties:
     serializedVersion: 3
     - _TexWorldScaleEmissive: 1
     - _Thickness: 1
     - _ThicknessMultiplier: 1
+    - _TransmissionEnable: 1
     - _TransparentBackfaceEnable: 0
     - _TransparentDepthPostpassEnable: 0
     - _TransparentDepthPrepassEnable: 0
     m_Colors:
     - _BaseColor: {r: 1, g: 1, b: 1, a: 1}
     - _Color: {r: 1, g: 1, b: 1, a: 1}
-    - _DoubleSidedConstants: {r: -1, g: -1, b: -1, a: 0}
+    - _DoubleSidedConstants: {r: 1, g: 1, b: 1, a: 0}
     - _EmissionColor: {r: 1, g: 1, b: 1, a: 1}
     - _EmissiveColor: {r: 0, g: 0, b: 0, a: 1}
     - _InvPrimScale: {r: 1, g: 1, b: 0, a: 0}