Do not output ViewportIndex on SPIR-V if GPU does not support it (#3644)

* Do not output ViewportIndex on SPIR-V if GPU does not support it

* Bump shader cache version

Ryujinx.Graphics.Shader/IGpuAccessor.cs

@@ -267,6 +267,15 @@ namespace Ryujinx.Graphics.Shader
             return true;
         }
 
+        /// <summary>
+        /// Queries host GPU shader viewport index output support.
+        /// </summary>
+        /// <returns>True if the GPU and driver supports shader viewport index output, false otherwise</returns>
+        bool QueryHostSupportsViewportIndex()
+        {
+            return true;
+        }
+
         /// <summary>
         /// Queries the point size from the GPU state, used when it is not explicitly set on the shader.
         /// </summary>

Ryujinx.Graphics.Shader/Translation/AttributeInfo.cs

@@ -78,6 +78,11 @@ namespace Ryujinx.Graphics.Shader.Translation
 
         public static bool Validate(ShaderConfig config, int value, bool isOutAttr)
         {
+            if (value == AttributeConsts.ViewportIndex && !config.GpuAccessor.QueryHostSupportsViewportIndex())
+            {
+                return false;
+            }
+
             return From(config, value, isOutAttr).IsValid;
         }