cmd/dist: remove prints during test registration

dist test should not print (especially to stdout) during test
registration.  This confuses other tools interacting with dist using
dist test --list, etc.

Change-Id: Ie4f82c13e49590c23a7a235d90ddbc4f5ed81e0b
Reviewed-on: https://go-review.googlesource.com/12487Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/cmd/dist/test.go

@@ -420,9 +420,9 @@ func (t *tester) registerTests() {
 			})
 			switch t.goos {
 			case "darwin":
-				fmt.Println("Skipping misc/cgo/testsovar test. See issue 10360 for details.")
+				// Skipping misc/cgo/testsovar test. See issue 10360 for details.
 			case "netbsd":
-				fmt.Println("Skipping misc/cgo/testsovar test. See issue 11654 for details.")
+				// Skipping misc/cgo/testsovar test. See issue 11654 for details.
 			default:
 				t.tests = append(t.tests, distTest{
 					name:    "testsovar",