os/signal: don't run TestTerminalSignal on Solaris

Fixes #22849

Change-Id: Icf7f07d0d1d0669f5db4943030588646c819c62a
Reviewed-on: https://go-review.googlesource.com/79495
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/os/signal/internal/pty/pty.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+// +build darwin dragonfly freebsd linux netbsd openbsd
 // +build cgo
 
 // Package pty is a simple pseudo-terminal package for Unix systems,

src/os/signal/signal_cgo_test.go

@@ -2,9 +2,11 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+// +build darwin dragonfly freebsd linux netbsd openbsd
 // +build cgo
 
+// Note that this test does not work on Solaris: issue #22849.
+
 package signal_test
 
 import (