Reverted required shader feature in the standard shader

Added Cull option to the simple lighting depth only pass

ScriptableRenderPipeline/LightweightPipeline/LWRP/Shaders/LightweightStandard.shader

             //--------------------------------------
             // GPU Instancing
             #pragma multi_compile_instancing
+            #pragma shader_feature _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A
 
             #pragma vertex ShadowPassVertex
             #pragma fragment ShadowPassFragment
             // -------------------------------------
             // Material Keywords
             #pragma shader_feature _ALPHATEST_ON
+            #pragma shader_feature _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A
 
             //--------------------------------------
             // GPU Instancing

ScriptableRenderPipeline/LightweightPipeline/LWRP/Shaders/LightweightStandardSimpleLighting.shader

 
             ZWrite On
             ColorMask 0
+            Cull[_Cull]
 
             HLSLPROGRAM
             // Required to compile gles 2.0 with standard srp library