[llvm] [LoongArch] Add relaxDwarfLineAddr and relaxDwarfCFA to handle the mutable label diff in dwarfinfo (PR #77728)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,2 @@
+if not "LoongArch" in config.root.targets:
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MaskRay wrote:

`not in`

https://github.com/llvm/llvm-project/pull/77728