do not requeue cancelled job

Do not requeue a batch job from slurmd daemon if it is killed while in
the process of being launched (a race condition introduced in v14.03.9).
This partially reverts commit 2bc9bc2901a0a5b85dfd550e3cb5b8512f2ad655
Merge branch 'slurm-14.03' into slurm-14.11

Conflicts:
	src/slurmd/slurmd/req.c