unix: remove stray TODO comment

This was addressed by CL 2816 for package syscall and the same comment
was deleted from asm_linux_386.s.

Same as CL 261458 for package syscall.

Change-Id: Ib5d86dbafb6766f9d8d523c6035e1f095f18e6ed
Reviewed-on: https://go-review.googlesource.com/c/sys/+/261460
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/unix/syscall_linux_386.go b/unix/syscall_linux_386.go
index 048d18e..c97c2ee 100644
--- a/unix/syscall_linux_386.go
+++ b/unix/syscall_linux_386.go
@@ -2,9 +2,6 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// TODO(rsc): Rewrite all nn(SP) references into name+(nn-8)(FP)
-// so that go vet can check that they are correct.
-
 // +build 386,linux
 
 package unix