[llvm] [openmp] [OpenMP][Offload] Add `LIBOMPTARGET_TREAT_ATTACH_AUTO_AS_ALWAYS` to treat `attach(auto)` as `attach(always)`. (PR #172382)

[via llvm-commits]

ronlieb wrote:

> Thanks @jplehr, for the test fix! But do you know why the buildbot did not send out a notification email about the failure?

these bots are in staging status. it would be beneficial to get them back into production

https://github.com/llvm/llvm-project/pull/172382