[llvm] [mlir] [mlir][Python] create MLIRPythonSupport (PR #171775)

[Maksim Levental via llvm-commits]

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@@ -46,6 +46,8 @@
 #define MLIR_CAPI_EXPORTED __attribute__((visibility("default")))
 #endif
 
+#define MLIR_PYTHON_API_EXPORTED MLIR_CAPI_EXPORTED
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makslevental wrote:

I think it makes sense to put this close to where MLIR_CAPI_EXPORTED is defined and also this header is used pretty much universally in all extensions. But if you think it would be better to have a separate set of macros for just Python I can factor this one out.

https://github.com/llvm/llvm-project/pull/171775