[Bug c++/117219] strict aliasing documentation maybe should mention C++20's std::bit_cast

[sjames at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117219

--- Comment #4 from Sam James <sjames at gcc dot gnu.org> ---
I'll also make it mention memcpy. It's what we tell people anyway, just for
some reason never came up in the docs.