IdleMaint: run more frequently during 3AM to 4AM

This patch makes IdleMaint trigger multiple times between
3AM and 4AM, if device is idle and power is not low. This
will not trigger until next 3AM.

Bug: 128594671
Change-Id: Id6596be44ff96d39f77fb21dca52c35952f2cf7e
Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>