CSI is now the preferred storage driver for Rook.
By default both the CSI and flex drivers will be started
by the operator. In a future release the flex driver
will be deprecated, but for now is still supported.

The drivers can be disabled with an environment
variable in the operator deployment in operator.yaml.
If users are only using one driver or the other there is
no need to enable both drivers.
Signed-off-by: travisn <tnielsen@redhat.com>