ioctl.test: robustify against libcs invoking ioctl syscall on their own
ioctl.test: robustify against libcs invoking ioctl syscall on their own

* tests/ioctl.test: Filter out from the log ioctl calls with standard
descriptor arguments.

Reported-by: Szabolcs Nagy <66dbfa9ac70d64a0115425cd5cf334835ba79b72@port70.net>

cuviper/strace,Saruta/strace,cuviper/strace,Saruta/strace,cuviper/strace,Saruta/strace,Saruta/strace,cuviper/strace,cuviper/strace,Saruta/strace