[libxml2] Fix unused variable warning in python/types.c

[Nick Wellnhofer <nwellnhof src gnome org>]

commit 75cdb6dd55c07d35ddc405ed66c8361c6922c5b9
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Fri Sep 2 16:47:25 2022 +0200

    Fix unused variable warning in python/types.c

 python/types.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/python/types.c b/python/types.c
index 8d690472..00e04d3b 100644
--- a/python/types.c
+++ b/python/types.c
@@ -82,8 +82,11 @@ libxml_PyFileGet(PyObject *f) {
     FILE *res;
     const char *mode;
 
-    int fd = PyObject_AsFileDescriptor(f);
+#ifdef _WIN32
     intptr_t w_fh = -1;
+#else
+    int fd = PyObject_AsFileDescriptor(f);
+#endif
 
 #ifdef _WIN32
     HMODULE hntdll = NULL;