If the worker segfaults, we may never see a TaskFailed event from it, only
a runQueueTaskFailed event. In this case, return_value isn't getting set
leading to an incorrect exit code from bitbake. Fix by setting return_value
in both places.
(Bitbake rev: e5dd50e0d95d532fe31dde61f8c6b1a7a72321e9)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>