remove xtrabackup_remote_host from default

Related: PROD-28004(PROD:28004)

Change-Id: I59116f031f9b56ac2e9ed4df092c547ae6001548
diff --git a/defaults/xtrabackup.yml b/defaults/xtrabackup.yml
index e2bf995..2920598 100644
--- a/defaults/xtrabackup.yml
+++ b/defaults/xtrabackup.yml
@@ -3,4 +3,3 @@
     xtrabackup_qpress_source: pkg
     xtrabackup_qpress_source_name: qpress
     xtrabackup_public_key: no-key-provided
-    xtrabackup_remote_server: cfg01