lisa.utils: Provide a dummy silent logger in __del__
lisa.utils: Provide a dummy silent logger in __del__

Calling the logging module in __del__ can lead to issues, so return a
dummy logger that will not do anything.

ARM-software/lisa,ARM-software/lisa,credp/lisa,ARM-software/lisa,credp/lisa,ARM-software/lisa,credp/lisa,credp/lisa