[clang] [flang] [llvm] [mlir] [TargetRegistry] Accept Triple in createTargetMachine() (NFC) (PR #130940)

[Matt Arsenault via cfe-commits]

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@@ -453,14 +453,14 @@ class Target {
   /// either the target triple from the module, or the target triple of the
   /// host if that does not exist.
   TargetMachine *createTargetMachine(
-      StringRef TT, StringRef CPU, StringRef Features,
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arsenm wrote:

Can we keep a StringRef overload, at least for a while? As-is this is going to break a lot of downstream builds 

https://github.com/llvm/llvm-project/pull/130940