Disable ExtractEnumConstants for OpenXR and Vulkan

Not necessary and causes incorrect output.

Author: Exanite

generator.json

@@ -575,7 +575,6 @@
         "MarkNativeNames",
         "ExtractHandles",
         "ExtractNestedTypes",
-        "ExtractEnumConstants",
         "ExtractFunctionPointers",
         "TransformHandles",
         "MixKhronosData",
@@ -702,7 +701,6 @@
         "MarkNativeNames",
         "ExtractHandles",
         "ExtractNestedTypes",
-        "ExtractEnumConstants",
         "ExtractFunctionPointers",
         "TransformHandles",
         "MixKhronosData",