Correct typo

setuptools/config.py

@@ -263,7 +263,7 @@ class ConfigHandler(object):
         filepaths = (os.path.abspath(path.strip()) for path in spec.split(','))
         return '\n'.join(
             self._read_local_file(path)
-            for path in filepath
+            for path in filepaths
             if os.path.isfile(path)
         )