torture: Exclude "NOHZ tick-stop error" from fatal errors

commit 8d68e68a

 upstream.

The "NOHZ tick-stop error: Non-RCU local softirq work is pending"
warning happens frequently and appears to be irrelevant to the various
torture tests.  This commit therefore filters it out.

If there proves to be a need to pay attention to it a later commit will
add an "advice" category to allow the user to immediately see that
although something happened, it was not an indictment of the system
being tortured.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tools/testing/selftests/rcutorture/bin/console-badness.sh

@@ -13,4 +13,5 @@
 egrep 'Badness|WARNING:|Warn|BUG|===========|Call Trace:|Oops:|detected stalls on CPUs/tasks:|self-detected stall on CPU|Stall ended before state dump start|\?\?\? Writer stall state|rcu_.*kthread starved for|!!!' |
 grep -v 'ODEBUG: ' |
 grep -v 'This means that this is a DEBUG kernel and it is' |
-grep -v 'Warning: unable to open an initial console'
+grep -v 'Warning: unable to open an initial console' |
+grep -v 'NOHZ tick-stop error: Non-RCU local softirq work is pending, handler'