This PR ensures that we can test our siderolink communication using embedded siderolink-agent. If `--with-siderolink` provided during `talos cluster create` talosctl will embed proper kernel string and setup `siderolink-agent` as a separate process. It should be used with combination of `--skip-injecting-config` and `--with-apply-config` (the latter will use newly generated IPv6 siderolink addresses which talosctl passes to the agent as a "pre-bind"). Fixes #8392 Signed-off-by: Dmitriy Matrenichev <dmitry.matrenichev@siderolabs.com>