Limit "walk" output for otel/SIM metrics

[Ryan Faircloth]

For Splunk Otel/SIM destinations do not send "walk" results as metrics treat these as logs only.

[Olga]

Since #479 small walk functionality has changed, so that we never do a full walk on a device if it is configured. It turned out, that some of the customers devices are so big that one full walk could take ~8 hours, what was exceeding all of the timeouts we had. Now otel/SIM can configure what to exactly walk, without unnecessary information.