[llvm] [memprof] Group MemProf data structures into a struct (NFC) (PR #92360)

[Kazu Hirata via llvm-commits]

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@@ -603,23 +592,17 @@ static Error writeMemProfV2(
 // uint64_t Schema entry N - 1
 // OnDiskChainedHashTable MemProfRecordData
 // OnDiskChainedHashTable MemProfFrameData
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kazutakahirata wrote:

Yes, thank you for pointing this out!  The comment needs to be updated in a version-specific manner.  Let me create a separate PR.

https://github.com/llvm/llvm-project/pull/92360