Plugin specs built by (*v2.Plugin).InitSpec never went through
daemon/internal/rootless/specconv.ToRootless, so the /sys fix-up
for network=host under detach-netns (added in 84aedb805 "rootless:
support detach-netns mode") was skipped for plugins. This made
`docker plugin install` fail in rootless mode.
Apply the same rootless conversion that container specs receive in
daemon/oci_linux.go, gated on rootless.RunningWithRootlessKit().
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
These utilities are very handy to use in integration tests, too. Move
the package so it can be imported by them.
Signed-off-by: Cory Snider <csnider@mirantis.com>
