net: fix typo

Change-Id: Ic828256efe0f50a3e11a25d85092d7531b342d2e
Reviewed-on: https://go-review.googlesource.com/19873Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/net/main_noconf_test.go

@@ -8,7 +8,7 @@ package net
 
 import "runtime"
 
-// See main_unix_test.go for what these (don't) do.
+// See main_conf_test.go for what these (don't) do.
 func forceGoDNS() func() {
 	switch runtime.GOOS {
 	case "plan9", "windows":
@@ -18,5 +18,5 @@ func forceGoDNS() func() {
 	}
 }
 
-// See main_unix_test.go for what these (don't) do.
+// See main_conf_test.go for what these (don't) do.
 func forceCgoDNS() func() { return nil }