runtime: remove the 'go:nosplit' directive from documentation
The //go:nosplit directive was visible in GoDoc because the function
that it preceeded (Gosched) is exported. This change moves the directive
above the documentation, hiding it from the output.
Change-Id: I281fd7573f11d977487809f74c9cc16b2af0dc88
Reviewed-on: https://go-review.googlesource.com/69120
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>