tlbstat: duration isn't implemented for the default "all CPUs" mode

[martinvonwittich]

./tlbstat 1 10

I had expected tlbstat to stop after 10 seconds, but instead it runs forever. This is due to the fact that sleep $duration is only passed to perf if the -C or -p option is given:

pmc-cloud-tools/tlbstat

Lines 70 to 73 in 5d4df1e

	target=-a
	(( opt_cpu )) && target="-C $cpu sleep $duration"
	(( opt_pid )) && target="-p $pid sleep $duration"
	(( opt_cmd )) && target="$cmd"