add os specific internal vars

handlers/main.yml

@@ -1,7 +1,7 @@
 ---
 - name: Restart ntpd
   service:
-    name: ntpd
+    name: "{{ __ntp_service_name }}"
     state: restarted
     enabled: yes
   listen: __ntpd_restart

tasks/main.yml

@@ -1,4 +1,8 @@
 ---
+- include_vars: "{{ item }}"
+  with_first_found:
+    - "os_{{ ansible_os_family | lower }}.yml"
+
 - include_tasks: setup_default.yml
   when:
     - common_sshd_configuration_enabled

vars/os_debian.yml

@@ -0,0 +1,2 @@
+---
+__ntp_service_name: ntp

vars/os_redhat.yml

@@ -0,0 +1,2 @@
+---
+__ntp_service_name: ntpd