ceph: fix CephFNS plurial
ceph: fix CephFNS plurial

Introducing the new flag to get the correct plurial version of CephNFS,
if not overriden the generator will be CephNFSs instead of CephNFSes.

We run deepcopy and client,lister,informer generations separetly so we can use the flag "--plural-exceptions"
which is only known by client,lister,informer binary and not the deepcopy binary.

Signed-off-by: Sébastien Han <62d754cc350e84d3b1c32ae79f976f5348e74a40@redhat.com>

rook/rook,rook/rook,rook/nfs,rook/rook,rook/nfs,rook/rook,rook/rook,rook/nfs