runtime: update deltimer comments
runtime: update deltimer comments

Change-Id: I5f4c21bf650b9825ebd98330ac9faa7371a562be
GitHub-Last-Rev: 4a2e9aabe91935001300619b6f58c67f05e9f3c7
GitHub-Pull-Request: golang/go#36728
Reviewed-on: https://go-review.googlesource.com/c/go/+/216223
Run-TryBot: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>

golang/go,cloudflare/go,CAFxX/go,golang/go,cloudflare/go,CAFxX/go,cloudflare/go,nawawi/go,cloudflare/go,CAFxX/go,CAFxX/go,CAFxX/go,akutz/go,nawawi/go,golang/go,akutz/go,nawawi/go,nawawi/go,CAFxX/go,nawawi/go,nawawi/go,golang/go,golang/go,cloudflare/go,cloudflare/go,cloudflare/go,akutz/go,akutz/go,akutz/go,golang/go,CAFxX/go,akutz/go,nawawi/go,golang/go,CAFxX/go,cloudflare/go,nawawi/go,akutz/go,akutz/go,golang/go