runtime: fix sigpipe do not check SIGPIPE was ignored

Fixes #32386

Change-Id: I29ad4113b02264336eebe7865895f07ef386f450
Reviewed-on: https://go-review.googlesource.com/c/go/+/180177
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/runtime/signal_unix.go

@@ -268,7 +268,7 @@ func setThreadCPUProfiler(hz int32) {
 }
 
 func sigpipe() {
-	if sigsend(_SIGPIPE) {
+	if signal_ignored(_SIGPIPE) || sigsend(_SIGPIPE) {
 		return
 	}
 	dieFromSignal(_SIGPIPE)