[llvm] [memprof] Add MemProf version (PR #86414)

[Snehasish Kumar via llvm-commits]

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@@ -15,6 +15,15 @@
 namespace llvm {
 namespace memprof {
 
+// The versions of the indexed MemProf format
+enum MemProfVersion {
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snehasish wrote:

Perhaps call this IndexedVersion so when we spell it out with the namespace (e.g. `memprof::IndexedVersion`) it's clear to the reader which format we are referring to?

https://github.com/llvm/llvm-project/pull/86414