storaged: add dumpsys flags to limit data size

--threshold <bytes>
This skips io usage not greater than <bytes> for current report.

--time_window <secs>
This sets uid_io collection interval to <secs> for future reports.
The new interval will be ignore if it's less than 5 minutes.

Test: adb shell dumpsys --threshold 4096 --time_window 300
Bug: 33086174
Bug: 34198239
Change-Id: I723c0850fa504a113da0a14945c4fbc64ea47659