setWebClientAtomicBoolLocked and setDebugLogsByCapabilityLocked
each only need the node capabilities to decide what to do, so
take a set.Set[tailcfg.NodeCapability] directly as part of
getting rid of netmap.NetworkMap.
Updates #12542
Change-Id: If7c30b6354fd42dfe82ed6d2e2fe3439de401315
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>