[libc++] NFC: Normalize `#endif //` comment indentation

GitOrigin-RevId: 4cd6ca102a94e1b64ba3f940cc26b4d7b2b82964
diff --git a/include/ios b/include/ios
index 653e3a9..0104b33 100644
--- a/include/ios
+++ b/include/ios
@@ -1037,4 +1037,4 @@
 
 _LIBCPP_END_NAMESPACE_STD
 
-#endif  // _LIBCPP_IOS
+#endif // _LIBCPP_IOS