S3-compatible storage solution for Loki with OpenShift Subscription

1. Proposed title of this feature request :

S3-compatible storage solution for Loki with OpenShift Subscription

2. What is the nature and description of the request?
   

The current logging stack is going to be replaced soon and ES is going to be replaced by Loki.  The problem here is that Loki requires S3 storage while Elasticsearch did not require it. This would be a problem for customers having OCP on vSphere. 

To purchase OpenShift Data Foundation can be one of the solutions. But it is very expensive. Customers need to pay additional cost just for OpenShift Logging.

3. Why does the customer need this? (List the business requirements here)

If customers have to purchase S3-compatible storage additionally just by this logging-stack migration, they might complain and stop using OpenShift4v. (Because they will think that Red Hat will put more burdens on them if they continued to use OpenShift4)

Purchasing ODF just for logging is an expensive option. 

4. List any affected packages or components.

Logging stack