
In https://review.openstack.org/534819 we introduced the removal of conflicting packages from the targeted host, but then we deleted the list for RedHat in https://review.openstack.org/578844 because yum kept removing and re-adding the same packages. In https://review.openstack.org/603205 we solve the issue properly given that yum is case-insensitive, and the root cause of the repeat remove/install. As such, in this patch, we restore the removal of conflicting packages for RedHat in a different way. Each of the package removal tasks are moved into the tasks specific to each package manager so that each can be handled differently. Change-Id: I70fbfa6eff8796713c6bec32319382273f8281f8 Related-Bug: #1762421 Related-Bug: #1742206