Fix windows only build failure on include filename.

Between eliding third_party directory names in includes, and Windows being case insensitive on header include paths, the following include was ambiguous and resolved to (1), leading to issues in using the StableHLO header:

```
#include "stablehlo/transforms/Passes.h"
// (1) tensorflow/compiler/mlir/lite/stablehlo/transforms/passes.h
// (2) @stablehlo - third_party/stablehlo/stablehlo/transforms/Passes.h
```

PiperOrigin-RevId: 679703637

xla/mlir_hlo/BUILD

@@ -1147,7 +1147,6 @@ cc_library(
     srcs = [
         "stablehlo_ext/transforms/chlo_recompose_ops.cpp",
         "stablehlo_ext/transforms/stablehlo_canonicalize_dynamism.cpp",
-        "stablehlo_ext/transforms/stablehlo_compatibility_expander.cpp",
         "stablehlo_ext/transforms/stablehlo_refine_shapes.cpp",
     ],
     hdrs = [

xla/mlir_hlo/stablehlo_ext/transforms/passes.h

@@ -32,12 +32,6 @@ namespace stablehlo_ext {
 
 void createChloLegalizeToStablehloPipeline(OpPassManager &pm);
 
-// Expand backward compatibility with the given StableHLO version by decomposing
-// newer StableHLO operations into equivalent operations supported by that older
-// version.
-std::unique_ptr<Pass> createStablehloCompatibilityExpanderPass(
-    std::string targetVersionOption);
-
 }  // namespace stablehlo_ext
 }  // namespace mlir