[flang] [clang] [flang][driver] Rename `flang-new` as `flang` (PR #74377)

[Fangrui Song via cfe-commits]

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@@ -27,7 +27,7 @@
 ! FULL-LTO: "-fc1"
 ! FULL-LTO-SAME: "-flto=full"
 
-! THIN-LTO-ALL: flang-new: warning: the option '-flto=thin' is a work in progress
+! THIN-LTO-ALL: flang-{{[0-9]+}}: warning: the option '-flto=thin' is a work in progress
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MaskRay wrote:

For Clang, lld, and LLVM binary utilities, our convention is to omit the part before `warning:`/`error:`. People may customize the `\d+` part and sometimes symlinks in certain build systems make this more complex.

https://github.com/llvm/llvm-project/pull/74377