[llvm] [utils] Add an alias name --cc for --clang (PR #69442)

[Alexander Richardson via llvm-commits]

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@@ -173,7 +173,7 @@ def config():
     )
     parser.add_argument("--llvm-bin", help="llvm $prefix/bin path")
     parser.add_argument(
-        "--clang", help='"clang" executable, defaults to $llvm_bin/clang'
+        "--cc", "--clang", help='"clang" executable, defaults to $llvm_bin/clang'
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arichardson wrote:

This changes the way the argument is accessed: it is now args.cc instead of args.clang so will break all tests.

https://github.com/llvm/llvm-project/pull/69442