[llvm] [AIX] Add git revision to .file string (PR #88164)

[Jake Egan via llvm-commits]

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@@ -0,0 +1,13 @@
+; Check that the git revision is contained in the assembly/object files
+
+; RUN: cd %S && git rev-parse HEAD > %t
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jakeegan wrote:

I've tried `llc --version`, but it doesn't return the revision unfortunately. I'll try to find some other ways. 

https://github.com/llvm/llvm-project/pull/88164