syscall: remove a wrong comment in Clearenv
The comment being removed was added by commit
ff3173849e
(which predates Gerrit and Rietveld, so no CL link), and
at the time it made sense.
Since CL
148370043 (and up to the current implementation of Clearenv)
the env map, which is populated by copyenv, is actually used, so the
comment is no longer valid.
It is also misleading, so it's best to remove it.
Change-Id: I8bd2e8bca6262759538e5bcbd396f0c71cca6a4c
Reviewed-on: https://go-review.googlesource.com/c/go/+/635078
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>