netaddr allocated at the time this was written. No longer.
name old time/op new time/op delta
TailscaleServiceAddr-4 5.46ns ± 4% 1.83ns ± 3% -66.52% (p=0.008 n=5+5)
A bunch of the others can probably be simplified too, but this
was the only one with just an IP and not an IPPrefix.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
