Remove reference to ntp package

This is motivated by the fact that NTP will be managed by
operators through the NTP charm. In the other Ceph charms,
NTP / Chrony are removed by the charm if the charm is in a
container because the ceph-base package will install it;
however, this is unneceessary for the radosgw package
because it doesn't depend on the ceph-common package.

Change-Id: I53ab9ece631bbaeed6e3cebba4ffbbcb1e32193d
Closes-Bug: #1915351

hooks/hooks.py

@@ -52,7 +52,6 @@ from charmhelpers.fetch import (
 from charmhelpers.payload.execd import execd_preinstall
 from charmhelpers.core.host import (
     cmp_pkgrevno,
-    is_container,
     service,
     service_pause,
     service_reload,
@@ -111,7 +110,6 @@ CONFIGS = register_configs()
 
 PACKAGES = [
     'haproxy',
-    'ntp',
     'radosgw',
     'apache2'
 ]
@@ -145,9 +143,6 @@ def install_packages():
         add_source(c.get('source'), c.get('key'))
         apt_update(fatal=True)
 
-    if is_container():
-        PACKAGES.remove('ntp')
-
     # NOTE: just use full package list if we're in an upgrade
     #       config-changed execution
     pkgs = (