OCPBUGS-36532: Agent installer wait-for, just test connectivity to host

In the agent wait-for, when the APIs are not available, an attempt is
made to check the host by ssh'ing to it. This results in confusing
debug messages if the keys aren't present. This changes the check to
just test connectivity to the host.

pkg/agent/cluster.go

@@ -6,7 +6,6 @@ import (
 	"net"
 	"os"
 	"path/filepath"
-	"strconv"
 	"time"
 
 	"github.com/go-openapi/strfmt"
@@ -17,7 +16,6 @@ import (
 	"github.com/openshift/assisted-service/models"
 	"github.com/openshift/installer/pkg/asset/agent/gencrypto"
 	"github.com/openshift/installer/pkg/asset/agent/workflow"
-	"github.com/openshift/installer/pkg/gather/ssh"
 )
 
 // Cluster is a struct designed to help interact with the cluster that is
@@ -483,14 +481,16 @@ func (czero *Cluster) PrintInstallStatus(cluster *models.Cluster) {
 	}
 }
 
-// CanSSHToNodeZero Checks if ssh to NodeZero succeeds.
+// CanSSHToNodeZero Checks if NodeZero is reachable.
 func (czero *Cluster) CanSSHToNodeZero() bool {
 	ip := czero.API.Rest.NodeZeroIP
 	port := 22
 
-	_, err := ssh.NewClient("core", net.JoinHostPort(ip, strconv.Itoa(port)), czero.API.Rest.NodeSSHKey)
+	conn, err := net.Dial("tcp", fmt.Sprintf("%s:%d", ip, port))
 	if err != nil {
 		logrus.Debugf("Failed to connect to the Rendezvous Host: %s", err)
+	} else {
+		conn.Close()
 	}
 	return err == nil
 }