lmkd: Fix usage of ro.lmk.kill_heaviest_task property

lmkd should use ro.lmk.kill_heaviest_task property to select between
algorithms for victim selection. Set ro.lmk.kill_heaviest_task default
value to false in order to keep it compatible with previous versions
of lmkd (killing the heaviest task is a new mechanism).

Bug: 77299493
Bug: 75322373
Change-Id: I78d2dc79d9c54e636c26665605518d9c87b535b3
Merged-In: I78d2dc79d9c54e636c26665605518d9c87b535b3
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
(cherry picked from commit 818b59b2)