Enable debug-level logging when any --debug-opts is set.

The current behavior is a bit unintuitive, as passing --debug-opts=<opt> enabled the debug option but doesn't the log verbosity to DEBUG unless --debug was also given.
As a result, the log.debug() output guarded by those options was silently discarded, making the options appear to do nothing.

So, when -debug-opts is set to a valid option at least, always enable debug-level logging