fix: this prevents possible loops while connecting (#521)

A recent change made it possible to get stuck in a loop when connecting
to a remote. This reverts the part of it that caused this while
retaining the other behavior. This makes it possible to add to blank
known_host files again. It also adds a printout to display when a
connection is complete.

wavesrv/pkg/remote/sshclient.go

@@ -390,7 +390,7 @@ func createHostKeyCallback(opts *sstore.SSHOpts) (ssh.HostKeyCallback, error) {
 	// incorrectly. if a problem file is found, it is removed from our list
 	// and we try again
 	var basicCallback ssh.HostKeyCallback
-	for len(knownHostsFiles) > 0 {
+	for basicCallback == nil && len(knownHostsFiles) > 0 {
 		var err error
 		basicCallback, err = knownhosts.New(knownHostsFiles...)
 		if serr, ok := err.(*os.PathError); ok {
@@ -412,10 +412,6 @@ func createHostKeyCallback(opts *sstore.SSHOpts) (ssh.HostKeyCallback, error) {
 		}
 	}
 
-	if basicCallback == nil {
-		basicCallback = func(hostname string, remote net.Addr, key ssh.PublicKey) error { return &knownhosts.KeyError{} }
-	}
-
 	waveHostKeyCallback := func(hostname string, remote net.Addr, key ssh.PublicKey) error {
 		err := basicCallback(hostname, remote, key)
 		if err == nil {