PREINSTALL_OMNIA_APPLIANCE.md documentation has errors

[j0hnL]

Describe the bug
Documentation for PREINSTALL appliance reads:

yum install ansible-2.9.17

This package is no longer available from EPEL, when using the current release from epel 2.9.18-1.el7 there is a problem with the way we query for SELinux:

The error appears to be in '/root/omnia/appliance/roles/common/tasks/pre_requisite.yml': line 30, column 3, but may
be elsewhere in the file depending on the exact syntax problem.

The offending line appears to be:


- name: Disable SElinux
  ^ here

To Reproduce
use the instructions at https://github.com/dellhpc/omnia/blob/devel/docs/PREINSTALL_OMNIA_APPLIANCE.md

Possible Fix
use pip to install the specific version of ansible if that version is needed
pip install ansible==2.9.17

get the latest version of ansible from yum 2.9.18-1 and install the galaxy collection for selinux using
ansible-galaxy collection install ansible.posix