Remove the statement that .TQ was "rarely used even in GNU manual pages".

Remove the statement that .TQ was "rarely used even in GNU manual pages".

It appears the Linux Manual Pages project started to quite aggressively
use .TQ ever for cases where it not only provides no value, but makes
formatting worse even when it formats as intended.  It's also a bad idea
to use it that aggressively because .TQ has particularly catastrophic
formatting behaviour on formatters (other than groff and mandoc) that do
not support it: It essentially has the effect of omitting the topic of
the discussion from the formatted version of the manual page, but in
such a way that it does not become apparent to the reader that anything
is missing.

But whether this is wise or stupid is their problem and none of our
business.  Either way, we should not call a thing "rarely used"
after that is no longer true.

Thanks to Alejandro Colomar <alx at kernel org org>
for making me aware that the statement is no longer true.