Squashed 'external/devlib/' changes from d4f331612..c212ef214

c212ef214 module/cgroups: Really move all tasks in Controller.move_all_tasks_to()
5b5da7c39 module/cgroups: log to the class' logger
3801fe1d6 trace-cmd: Respect `strict` when setting `saved_cmdlines_size`
43673e3fc ftrace: Report unavailable events all at once
bbe3bb6ad ftrace: Expose FtraceCollector.available_events
656da00d2 ftrace: Add tracer name validation
6b0b12d83 ftrace: Enable alternative tracers
56cdc2e6c ftrace: Allow setting the number of cmdlines saved by ftrace
def235064 ftrace: Allow choosing clock source
4d1299d67 Target: Allow for any `TargetError` when checking for root

git-subtree-dir: external/devlib
git-subtree-split: c212ef21466bb3d8ff5633f3a5bc53777be2b63a