wgengine/netstack: remove old unused handleSSH hook
It's leftover from an earlier Tailscale SSH wiring and I forgot to
delete it apparently.
@@ -127,10 +127,6 @@ type Impl struct {
connsOpenBySubnetIP map[netip.Addr]int
}
-// handleSSH is initialized in ssh.go (on Linux only) to register an SSH server
-// handler. See https://github.com/tailscale/tailscale/issues/3802.
-var handleSSH func(logger.Logf, *ipnlocal.LocalBackend, net.Conn) error
-
const nicID = 1
const mtu = tstun.DefaultMTU
