btaa: Add device-activity aggregation dumpsys data

1. Add create time into each aggregation entry; aggregation entry
expires after one day.
2. Add device-activity into dumpsys data; Trim down transient
aggregation entries to avoid the unordered map overgrows.

Tag: #feature

Bug: 185819535
Bug: 170315554

Test: mmma -j system/bt
Test: manually capture a bugreport and make sure btaa aggregation data
show up

BYPASS_LONG_LINES_REASON: consist with gd format

Change-Id: I02cc2057796661fa3625492eaf1a429e20da4951