Revert "SSHKeysHelper: print "RSA PRIVATE KEY" instead of "PRIVATE KEY""

This reverts commit 960d2aa445a9adf5c0c71c800c40625359cb4c6e.

Author: weizhouapache

utils/src/main/java/com/cloud/utils/ssh/SSHKeysHelper.java

@@ -20,7 +20,6 @@
 package com.cloud.utils.ssh;
 
 import java.io.ByteArrayOutputStream;
-import java.io.StringWriter;
 import java.math.BigInteger;
 import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
@@ -32,8 +31,6 @@
 
 import org.apache.cloudstack.utils.security.CertUtils;
 import org.apache.commons.codec.binary.Base64;
-import org.bouncycastle.util.io.pem.PemObject;
-import org.bouncycastle.util.io.pem.PemWriter;
 
 public class SSHKeysHelper {
 
@@ -149,12 +146,7 @@ public String getPrivateKey() {
             return null;
         }
         try {
-            final PemObject pemObject = new PemObject("RSA PRIVATE KEY", keyPair.getPrivate().getEncoded());
-            final StringWriter sw = new StringWriter();
-            try (final PemWriter pw = new PemWriter(sw)) {
-                pw.writeObject(pemObject);
-            }
-            return sw.toString();
+            return CertUtils.privateKeyToPem(keyPair.getPrivate());
         } catch (Exception e) {
             e.printStackTrace();
         }