Allow the override of pacemaker::corosync::settle_tries

Allow the override of pacemaker::corosync::settle_tries

When replacing a controller node, Exec['wait-for-settle'] needs to
timeout, which means that the command pcs cluster auth will be executed
360 times with 10 seconds in between. So that means waiting for an hour
for no reason. Let's allow to override the settle_tries counter so
an operator can shorten it accordingly.

Tested this by setting CorosyncSettleTries to 100 and I correctly get
proper hiera settings:
$ hiera pacemaker::corosync::settle_tries
100

And effectively we try a number of 100 times as opposed to the 360
default:
/Stage[main]/Pacemaker::Corosync/Exec[reauthenticate-across-all-nodes]/returns
(debug): Exec try 1/100

Change-Id: I5e21b4215cb0b8686d2059b3d71e2444a96719dc
Closes-Bug: #1659741