[llvm] [OFFLOAD] Extend olMemRegister API to handle cases when a memory block may have been mapped outside of liboffload. (PR #172226)

[Kevin Sala Penades via llvm-commits]

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@@ -167,12 +177,13 @@ def olMemUnregister : Function {
   let desc = "Unregister and page-unlock host memory.";
   let details = [
         "Unpins host memory that was previously pinned or unregister the buffer",
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kevinsala wrote:

`Unregisters host memory and optionally page-unlocks it...`

https://github.com/llvm/llvm-project/pull/172226