Explain why attempts to remove the libc++ dependency are futile.

This isn't as useless as it seems though. It should prevent me from
going down this path a third time, and it removes one pointless barrier
that gets in the way of running a toybox binary on an older release.

Change-Id: Ia193eb7af162878a331db1b1e1c90ff0f617becb
1 file changed