[llvm] [BOLT][NFC] Add sink block to flow CFG in profile inference (PR #95047)

[Maksim Panchenko via llvm-commits]

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@@ -57,6 +58,7 @@ struct FlowFunction {
   std::vector<FlowJump> Jumps;
   /// The index of the entry block.
   uint64_t Entry{0};
+  uint64_t Sink{0};
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maksfb wrote:

Nit: add a description and initialize to `uint64_t` max value to indicate that a proper initialization will happen later.

https://github.com/llvm/llvm-project/pull/95047