[clang] [clang-linker-wrapper] Add error handling for missing linker path (PR #113613)

[Joseph Huber via cfe-commits]

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@@ -370,6 +370,8 @@ Error runLinker(ArrayRef<StringRef> Files, const ArgList &Args) {
   // Render the linker arguments and add the newly created image. We add it
   // after the output file to ensure it is linked with the correct libraries.
   StringRef LinkerPath = Args.getLastArgValue(OPT_linker_path_EQ);
+  if (LinkerPath.empty())
+    return createStringError("Host linker is not available");
----------------
jhuber6 wrote:

```suggestion
    return createStringError("linker path missing, must pass 'linker-path'");
```

https://github.com/llvm/llvm-project/pull/113613