Adjust test. You're not supposed to change errno in a signal handler and

Adjust test.  You're not supposed to change errno in a signal handler and
count on it being observable in the normal program flow after the signal
handler returns.  Such code would break code that sets errno to 0 and
looks at its value later.  With the recent futex(2) changes this particular
aspect of the test no longer passed.

ok deraadt@, bluhm@