All implementations of these functions are identical.

Follow CL 30819 which did the same for syscall.

Change-Id: I3c78f05ea12251306f3e100a006d266154a5238e
Reviewed-on: https://go-review.googlesource.com/72378
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>