mgr/telemetry: pass leaderboard flag even w/o ident

mgr/telemetry: pass leaderboard flag even w/o ident

Allow non-identified clusters to appear in the leaderboard.
The leaderboard option still defaults to false, so the change here
is that if they opt in to leaderboard but not ident we'll see
that on the backend.

Note that a leaderboard still does not exist (yet), so this doesn't
have any immediate impact.  But if/when we do create one, it will
allow us to show big clusters (that opt in) on the leaderboard
as 'unidentified' or similar.

Signed-off-by: Sage Weil <sage@newdream.net>