[lld] [llvm] [LIT][LLD] Fix Windows test failures due to path separator mismatches (PR #179865)

[Martin Storsjö via llvm-commits]

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@@ -17,6 +17,9 @@ def map_config(source_dir, site_config):
 # configuration file knows how to find the object tree.
 builtin_parameters = { 'build_mode' : '@BUILD_MODE@' }
 
+if "@LLVM_WINDOWS_PREFER_FORWARD_SLASH@".upper() in ["ON", "TRUE", "1"]:
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mstorsjo wrote:

I think the common practice for things like this, is to normalize the variable on the cmake side, before substituting it into the lit scripts. Grep for `pythonize_bool` for existing examples. Alternatively there's also a lit helper function, `lit.util.pythonize_bool()` which also can be used.

https://github.com/llvm/llvm-project/pull/179865