[Samba 4] smbtorture BENCH-NBENCH returns a (seemingly) false failure

[Kaplan, Marc]

Tridge,

I'm found that when I run smbtorture --num-progs>1 (i.e. --num-progs 20)
smbtorture gets a false "TEST BENCH-NBENCH FAILED!" message. At least it
seems like this is a false failure, since the test completes
successfully. 

I just put a few debug printfs and tracked it down to this conditional
in source/torture/torture.c: 
if (ret == -1 || WEXITSTATUS(status) != 0) 

My debug print was tripped once for each prog in --num-progs. If I set
--num-progs=1, I don't have this problem.

		-Marc