[llvm] [AsmParser][MCA] Fix handling of multi-character comments (PR #147228)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,10 @@
+	// REQUIRES: aarch64-registered-target
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MaskRay wrote:

This comment still looks vague... `//` is the universal comment marker, but AArch64 sets `CommentString` to `//`, so it will print `//`.
However, it seems that this MC test passes even before this change.

I don't think `// RUN: llvm-mc -preserve-comments -n -triple aarch64 %s -o %t` (removed unneeded `<` and used `-o` for more conventional tests) needs to be indented

https://github.com/llvm/llvm-project/pull/147228