fb_systemd: drop systemd-timesyncd package installation

Summary: This package in Fedora was subsumed by udev a long time ago, let's stop attempting to install it.

Differential Revision: D59654432

fbshipit-source-id: 2bf275d055c4e182fde5272a26822f576f644518

cookbooks/fb_systemd/recipes/default_packages.rb

@@ -60,7 +60,8 @@
        !['trusty', 'jessie'].include?(node['lsb']['codename'])
       systemd_packages << 'systemd-journal-remote'
     end
-    if node['fb_systemd']['timesyncd']['enable']
+    if node['fb_systemd']['timesyncd']['enable'] &&
+        node['platform_family'] == 'debian'
       systemd_packages << 'systemd-timesyncd'
     end
     if node['packages'] && node['packages']['systemd']['version']