Some parentheses were missing making the rend_max_intro_circs_per_period()
return a lower value than it was suppose to.
The calculation is that a service at most will open a number of intro points
that it wants which is 3 by default or HiddenServiceNumIntroductionPoints. Two
extra are launched for performance reason. Finally, this can happen twice for
two descriptors for the current and next time period.
From:
2 * n_intro_wanted + 2
...which resulted in 8 for 3 intro points, this commit fixes it to:
(n_intro_wanted + 2) * 2
... resulting in 12 possible intro point circuit which is the correct maximum
intro circuit allowed per period.
Last, this commit rate limits the the log message if we ever go above that
limit else over a INTRO_CIRC_RETRY_PERIOD, we can print it often!
Fixes#22159
Signed-off-by: David Goulet <dgoulet@torproject.org>