<bits/move.h> provides std::forward, std::move, and std::swap. These are
defined to come from <utility> and not <algorithm>.
In c++11 and later std::swap comes from <utility>, previously it came from
<algorithm>. Fortunately, <bits/move.h> is a c++11 only header, so if any
symbols are being seen in it, that's where they should come from.
No test for this because mappings are non-portable.
This was reported in #486.