Ignore HNS networks with type Private
Fix #33052 (workaround style)
**- What I did**
HNS reports networks that don't have anything to do with the Daemon, and
for which no networking plugin is available. This make the Daemon start
sequence pause for 15 secs, as the plugin resolving logic has a wait &
retry logic
**- How I did it**
Just after retrieving the HNS networks, I filter out those with type
`Private`
**- How to verify it**
Replace dockerd coming with Docker for Windows from one built from this
PR. Windows containers daemon should now launch pretty quickly
Signed-off-by: Simon Ferquel <simon.ferquel@docker.com>