When parsing a config file, all settings derived from command line flags are
discarded because only the config settings are used. That has been the
traditional behavior for non-logging flags.
But `--config ... -v=4` used to work until
71ef0dafa7 added logging to the configuration.
To restore the original behavior, kube-proxy now:
- parses flags
- reads the config file
- applies logging settings from the flags to the config loaded from file
- uses that merged config