Switching ntp class to use new format for ntp servers definition

Prod related: (PROD:26561)

Change-Id: I75a6db76eae5e3991a0547f2e9ee2d9b8c07d5b0
diff --git a/ntp/client/single.yml b/ntp/client/single.yml
index 80e70d9..b015efa 100644
--- a/ntp/client/single.yml
+++ b/ntp/client/single.yml
@@ -1,5 +1,5 @@
 classes:
-- service.ntp.client
+- service.ntp.client.single
 parameters:
   ntp:
     client: