Fix crash in setup_files() if no files are defined

Commit 002fe73409d1e moved the division by o->nr_files outside
of the file loop, so for error cases we could end up with
doing the division without having files defined. Crash ensues.

Signed-off-by: Jens Axboe <axboe@fb.com>
Merge branch 'master' of ssh://git.kernel.dk/data/git/fio
Fixup --timeout command line option

Ensure we properly parse the time, use check_str_time()
instead of atoi(). Propagate the timeout correctly to
new jobs.

Signed-off-by: Jens Axboe <axboe@fb.com>
Support limited mixed command line options and job file

With this, you can now do:

$ fio --timeout=10s --time_based=1 jobfile.fio

and have the command line options work as if they were part
of the global section of jobfile.fio

Note that more advanced uses, like:

$ fio --option_foo=1 jobfile.fio --option_bar=1 jobfile2.fio

will not work, we still clear to default options for
subsequent jobs.

Signed-off-by: Jens Axboe <axboe@fb.com>