lmkd: add live-lock killer daemon

llkd needs the ability to forcibly crash the kernel if
cause is unlikely to result in an orderly shutdown. It
also needs to scan /proc/<pid> for additional process
information.

Test: lmkd_unit_test --gtest_filter=llkd.*
Bug: 33808187
Change-Id: I7f158a13814e79d5ec71fe90dbc7461abb521945