net/SocketUtil: use SocketDescriptor::SetBoolOption()

src/net/SocketUtil.cxx

@@ -42,9 +42,7 @@ socket_bind_listen(int domain, int type, int protocol,
 		throw MakeSocketError("Failed to listen on socket");
 
 #if defined(HAVE_STRUCT_UCRED) && defined(SO_PASSCRED)
-	const int pass_cred = 1;
-	setsockopt(fd.Get(), SOL_SOCKET, SO_PASSCRED,
-		   (const char *) &pass_cred, sizeof(pass_cred));
+	fd.SetBoolOption(SOL_SOCKET, SO_PASSCRED, true);
 #endif
 
 	return fd;