deprecate native_bin magic

[nkraetzschmar]

The native_bin hack provides acceleration for cross-arch builds.
Originally this was needed for two main reasons:

• Build arm64 images on x86 github runners
• Build x86 images locally on arm macbooks

Now with github hosted arm runners and podman machine on mac using rosetta instead of qemu by default (which has far far better emulation performance, and so far no random seg faults) this should no longer be required.

Deprecating this will both simplify the internals of the builder and may even provide a slight build time reduction on native builds, since the native_bin step cannot be skipped in its current design, even for native builds.

Note

While this would NOT deprecate or break cross-arch builds on container hosts without rosetta, however, on such hosts build performance would be degraded.

[fwilhe]

Totally forgot about rosetta for podman machine. Seems like I'm using it without noticing, but I don't often attempt to build x86 on my mac.

Really cool.

One question on github hosted runners: I believe that not everyone is yet able to use those (seems like I can't in my personal namespace, only in the gl org), so this means we make the situation worse for people using the builder outside of our org, right? @nkraetzschmar Are you aware of any timeline from github for when everyone is able to use hosted arm runners?