Fix socket mapping socket mapping nits

Fixes nits that were suggested in containers#20420. The caller of
`ListenAndWaitOnSocket` did not use the value returned by the conn
channel, therefore it was better to just close the conn in the
`ListenAndWaitOnSocket` function instead.

[NO NEW TESTS NEEDED]

Signed-off-by: Jake Correnti <jakecorrenti+github@proton.me>

pkg/machine/applehv/machine.go

@@ -669,24 +669,14 @@ func (m *MacMachine) Start(name string, opts machine.StartOptions) error {
 	}
 
 	logrus.Debug("waiting for ready notification")
-	var conn net.Conn
 	readyChan := make(chan error)
-	connChan := make(chan net.Conn)
-	go machine.ListenAndWaitOnSocket(readyChan, connChan, readyListen)
+	go machine.ListenAndWaitOnSocket(readyChan, readyListen)
 
 	if err := cmd.Start(); err != nil {
 		return err
 	}
 
 	err = <-readyChan
-	conn = <-connChan
-	if conn != nil {
-		defer func() {
-			if closeErr := conn.Close(); closeErr != nil {
-				logrus.Error(closeErr)
-			}
-		}()
-	}
 	if err != nil {
 		return err
 	}

pkg/machine/hyperv/vsock.go

@@ -274,16 +274,7 @@ func (hv *HVSockRegistryEntry) Listen() error {
 	}()
 
 	errChan := make(chan error)
-	connChan := make(chan net.Conn)
-	go machine.ListenAndWaitOnSocket(errChan, connChan, listener)
-	conn := <-connChan
+	go machine.ListenAndWaitOnSocket(errChan, listener)
 
-	if conn != nil {
-		defer func() {
-			if err := conn.Close(); err != nil {
-				logrus.Error(err)
-			}
-		}()
-	}
 	return <-errChan
 }

pkg/machine/sockets.go

@@ -30,16 +30,20 @@ func ReadySocketPath(runtimeDir, machineName string) string {
 // ListenAndWaitOnSocket waits for a new connection to the listener and sends
 // any error back through the channel. ListenAndWaitOnSocket is intended to be
 // used as a goroutine
-func ListenAndWaitOnSocket(errChan chan<- error, connChan chan<- net.Conn, listener net.Listener) {
+func ListenAndWaitOnSocket(errChan chan<- error, listener net.Listener) {
 	conn, err := listener.Accept()
 	if err != nil {
 		errChan <- err
-		connChan <- nil
 		return
 	}
 	_, err = bufio.NewReader(conn).ReadString('\n')
+
+	if closeErr := conn.Close(); closeErr != nil {
+		errChan <- closeErr
+		return
+	}
+
 	errChan <- err
-	connChan <- conn
 }
 
 // DialSocketWithBackoffs attempts to connect to the socket in maxBackoffs attempts