This makes the web server running inside tailscaled on 100.100.100.100:80 support requests with `Host: 100.100.100.100:80` and its IPv6 equivalent.
Prior to this commit, the web server replied to such requests with a redirect to the node's Tailscale IP:5252.
Fixes https://github.com/tailscale/tailscale/issues/14415
Signed-off-by: Alex Klyubin <klyubin@gmail.com>