ceph filesystem: correct log message
ceph filesystem: correct log message

Downing filesystem is incorrectly logged as removing filesystem.

Signed-off-by: Ramana Raja <1313a362c0d8582c598799adfe7f06a7b14e2f97@redhat.com>

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