[llvm] Allow .alt_entry symbols to pass the .cfi nesting check (PR #82268)

[Fangrui Song via llvm-commits]

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@@ -8,6 +8,8 @@
 	.p2align	2
 _locomotive:
 	.cfi_startproc
+	.alt_entry _engineer
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MaskRay wrote:

Add a comment that a `N_ALT_ENTRY` symbol can be in the middle of a subsection?

https://github.com/llvm/llvm-project/pull/82268