runtime/debug: fix minor BuildSetting doc typos
Corrects a couple of defined key descriptions.
Change-Id: I8c5c0e3aca5431086076d19792291aee96f5d1d5
GitHub-Last-Rev:
e722d0a923f6c556cbc7fd52f21862844538d75b
GitHub-Pull-Request: golang/go#62273
Reviewed-on: https://go-review.googlesource.com/c/go/+/522875
Reviewed-by: Bryan Mills <bcmills@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>