Moved duplicated BackbufferTransferFunction enum to a common enums file

Runtime/Common/FfxEnums.cs

@@ -0,0 +1,9 @@
+namespace FidelityFX
+{
+    public enum BackbufferTransferFunction
+    {
+        LDR_sRGB,
+        HDR_PQ,
+        HDR_scRGB,
+    }
+}

Runtime/Common/FfxEnums.cs.meta

@@ -0,0 +1,11 @@
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Runtime/FrameInterpolation/FrameInterpolation.cs

@@ -98,13 +98,6 @@ namespace FidelityFX.FrameGen
                 }
             }
         }
-        
-        public enum BackbufferTransferFunction
-        {
-            LDR_sRGB,
-            HDR_PQ,
-            HDR_scRGB,
-        }
 
         [Flags]
         public enum InitializationFlags

Runtime/OpticalFlow/OpticalFlow.cs

@@ -44,13 +44,6 @@ namespace FidelityFX.FrameGen
             public Vector2 MinMaxLuminance;
         }
 
-        public enum BackbufferTransferFunction
-        {
-            LDR_sRGB,
-            HDR_PQ,
-            HDR_scRGB,
-        }
-
         public static Vector2Int GetOpticalFlowTextureSize(Vector2Int displaySize)
         {
             return GetOpticalFlowTextureSize(displaySize, MinBlockSize);