dxgitrace: Support undocumented use counted interfaces.

DXCap seems to rely on these to keep track of objects, and apitrace will
crash trying to trace DXCap if it doesn't understand them.
diff --git a/specs/scripts/cxx2api.py b/specs/scripts/cxx2api.py
index 95986eb..d02b6ec 100755
--- a/specs/scripts/cxx2api.py
+++ b/specs/scripts/cxx2api.py
@@ -467,7 +467,7 @@
         location = decl.location
         if location is None:
             return False
-        return os.path.basename(location.file_name) in args
+        return os.path.basename(location.file_name) in map(os.path.basename, args)
 
     module, _ = os.path.splitext(main_header)
     visitor = decl2_dumper_t(module)