[llvm] [lit] Prevent "lld" from being substituted by LIT in llvm-driver tests (PR #191893)

[via llvm-commits]

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@@ -892,16 +892,20 @@ def use_lld(self, additional_tool_dirs=[], required=True, use_installed=False):
         was_found = ld_lld and lld_link and ld64_lld and wasm_ld
         tool_substitutions = []
         if ld_lld:
-            tool_substitutions.append(ToolSubst(r"ld\.lld", command=ld_lld))
+            if "ld.lld" not in no_substitutions:
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zeroomega wrote:

I redid the regex to exclude the "-flavor" and exclude "var=name"
Doing test runs now. Please take a look.

https://github.com/llvm/llvm-project/pull/191893