[llvm] [BOLT] Add --custom-allocation-vma flag (PR #136385)

[Maksim Panchenko via llvm-commits]

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@@ -237,6 +237,12 @@ UseGnuStack("use-gnu-stack",
   cl::ZeroOrMore,
   cl::cat(BoltCategory));
 
+static cl::opt<uint64_t> CustomAllocationVMA(
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maksfb wrote:

Do you want this flag to be at the top level or hidden?

https://github.com/llvm/llvm-project/pull/136385