more setup.py cleanup

setup.py

@@ -31,10 +31,10 @@ else:
 
 def get_extension_modules():
     return [Extension('pypocketfft',
-            sources=['pypocketfft.cc'],
-            include_dirs=include_dirs,
-            extra_compile_args=extra_compile_args,
-            extra_link_args=python_module_link_args)]
+                      sources=['pypocketfft.cc'],
+                      include_dirs=include_dirs,
+                      extra_compile_args=extra_compile_args,
+                      extra_link_args=python_module_link_args)]
 
 
 setup(name='pypocketfft',