Fix stdin being closed by mistake

This was closing the sockpair* sockets before they were initialised to INVALID_SOCKET.

Close #1823. Thanks to ostkamp.

lib/mosquitto.c

@@ -113,6 +113,8 @@ struct mosquitto *mosquitto_new(const char *id, bool clean_start, void *userdata
 #ifdef WITH_THREADING
 		mosq->thread_id = pthread_self();
 #endif
+		mosq->sockpairR = INVALID_SOCKET;
+		mosq->sockpairW = INVALID_SOCKET;
 		rc = mosquitto_reinitialise(mosq, id, clean_start, userdata);
 		if(rc){
 			mosquitto_destroy(mosq);
@@ -123,10 +125,6 @@ struct mosquitto *mosquitto_new(const char *id, bool clean_start, void *userdata
 			}
 			return NULL;
 		}
-		if(net__socketpair(&mosq->sockpairR, &mosq->sockpairW)){
-			log__printf(mosq, MOSQ_LOG_WARNING,
-					"Warning: Unable to open socket pair, outgoing publish commands may be delayed.");
-		}
 	}else{
 		errno = ENOMEM;
 	}