In some jobs, we run tests that use "rbd map".
On older kernels, this will not work if newer
RBD features are used. (Specifically, fast-diff
on bionic.)
On older distros, enable fewer features by default.
Closes-Bug: #1921897
Change-Id: Iff1c5210b0279379eb9612b206bdf456dd6f132e
(cherry picked from commit 35e1ff5cf4)