Restart services if handler called

Restart services if handler called

This patch fixes an issue where if hosts have different service lists,
it will prevent restarting changes on services that run later on.

For example, hostA in the mons and rgws group would initiate a config
change and restart of services on all mons and rgws hosts, even though
a separate hostB (which is only in the rgws group) has not had its
configuration changed yet. Additionally, when the second host has its
coniguration changed as part of the ceph-rgw role, it will not initiate
a restart since its inventory name != the first hosts.

To fix this we should run the restart once (using run_once: True)
as long as the host has called the handler. This will ensure that even
if only 1 host has called the handler it will initiate a restart on all
hosts that have called the handler.

Additionally, we add a var that is set when the handler runs, this will
ensure that only hosts that have called the handler get restarted.

Includes minor fix to remove unrequired "inventory_hostname in
play_hosts" when: clause. This is no longer required since the handlers
were changed. The host calling the handler will be in play_hosts
already.

(cherry picked from commit 59a4335a5639c9be12ee8a23805aaa14882b077e)
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1548357