The current behavior of the hardening role is to install the
epel-release package on all deployments. This patch changes
the logic to only install the EPEL repository if the deployer
has asked for ClamAV to be installed.
The patch also provides an option to disable the installation
of EPEL entirely using a variable.
Closes-Bug: 1702167
Change-Id: I9c5e6048f95636faf2a6d71ac9217ba69ca41296
a64c833a71