Add command for dump_power to create thismeal.txt
from thismeal.bin.
Support BatteryMitigationService to monitor
brownout event and generate thismeal.bin.
Test: /vendor/bin/hw/battery_mitigation -d
Bug: 293899466
Change-Id: I3fcbd62af25204a7469dd3952a91cd6d281bccd7
Signed-off-by: samou <samou@google.com>