[clang] [Clang][Driver] Add option to provide path for multilib's YAML config file (PR #109640)

[via cfe-commits]

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@@ -1,79 +1,79 @@
-// RUN: %clang -print-multi-flags-experimental --target=aarch64-linux -fc++-abi=itanium -fsanitize=address | FileCheck --check-prefix=CHECK-LINUX %s
+// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-linux -fc++-abi=itanium -fsanitize=address | FileCheck --check-prefix=CHECK-LINUX %s
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ArcaneNibble wrote:

Do you actually need to add this argument in this file? The file is only testing the flags and not the chosen final path, so the (lack of) YAML file should have no effect (`--sysroot=` isn't passed)

https://github.com/llvm/llvm-project/pull/109640