RemoteLinux: Use an SshProcess for rsync

Otherwise, if connection sharing is disabled and public key
authentication fails, the askpass tool is not invoked.

Change-Id: Iea8316675b8f270c924f822f340f6282b21450d5
Reviewed-by: hjk <hjk@qt.io>

src/plugins/remotelinux/rsyncdeploystep.cpp

@@ -69,7 +69,7 @@ private:
 
     mutable QList<DeployableFile> m_deployableFiles;
     bool m_ignoreMissingFiles = false;
-    QProcess m_rsync;
+    SshProcess m_rsync;
     SshRemoteProcessPtr m_mkdir;
 };