torture: Add "--no-" as synonym for "--do-no-" in torture.sh

In order to (for example) omit the real-time testing that torture.sh would
otherwise carry out, you put "--do-no-rt" on the torture.sh command line.
This works, but it is all too easy to instead type "--no-rt".  This is
unambiguous and easier to type, so this commit therefore allows all
"--no-" arguments as synonyms for their "--do-no-" counterparts.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>