[Bug other/67300] -foffload* undocumented

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67300

--- Comment #3 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Patch to document -foffload=
  https://gcc.gnu.org/pipermail/gcc-patches/2021-June/573081.html

Still undocumented:
  -foffload-abi=[lp64|ilp32]