Fixup manila-cephfs native backend defaults

Fixup manila-cephfs native backend defaults

The puppet-tripleo side for manila-cephfs landed without specifying
defaults for all class params [1] so when cephfs isn't enabled
e.g. only generic, then you will get errors for those params. See
review comments at [2] for reports of this.

This will fixup the manila-cephfs puppet-tripleo side to be more
in line with the tidy up adding netapp at [3]. The config is all
moved tripleo-heat-templates side. The tht review for this
is at https://review.openstack.org/#/c/358525/ and that will now
depend on this review.

[1] https://review.openstack.org/#/c/354047/
[2] https://review.openstack.org/#/c/354019/
[3] https://review.openstack.org/#/c/354014/
Change-Id: I918f6f23ae0bd3542bcfe1bf0c797d4e6aa8f4d9