Merge pull request #15199 from jsafrane/gluster-auto-unmount

Automatic merge from submit-queue

UPSTREAM: 48709: glusterfs: retry without auto_unmount only when it's not supported

This reduces time that OpenShift waits for gluster timeouts to one half (!) - it does not blindly try twice.

fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1466249

Author: openshift-merge-robot