[llvm] [MC][AArch64][ARM][X86] Push target-dependent assembler flags into targets (PR #139844)

[Fangrui Song via llvm-commits]

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@@ -50,14 +50,6 @@ enum MCSymbolAttr {
   MCSA_Memtag,                  ///< .memtag (ELF)
 };
 
-enum MCAssemblerFlag {
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MaskRay wrote:

Nice! I agree that it's better to handle these very target-specific flags into XXXTargetStreamer

https://github.com/llvm/llvm-project/pull/139844