Fix podman package for Darwin/Linux platform compatibility

[Gussy]

Installing podman on macOS currently fails as the release package structure changed.

❯ hermit install podman
fatal:hermit: podman-5.7.0: no binaries found matching "/Users/.../Library/Caches/hermit/pkg/podman-5.7.0/podman" - this may indicate a corrupted or misconfigured package, try removing /Users/.../Library/Caches/hermit/pkg/podman-5.7.0 and hermit will reinstall it (may require sudo)

This fixes the issue for 5.7.0, although previous versions were untested.