storaged: add task io to dump service

Display task io in dump service when both kernel logs task io to
proc/uid_io/stats and when debug flag is enabled.

Also add -t flag to display both uid and task io for storaged.

Tests:
adb shell
dumpsys storaged --debug
storaged -t

Bug: 63739275

Change-Id: If0c9814892ad61b790baa6395649af10b11d5b7c