krbd was being tested with filestore, up until recently when the
default for osd_objectstore was changed to bluestore. This broke
rbd_simple_big.yaml because bluestore_block_size defaults to 10G.
Pick up the sepia setting of 90G from bluestore-bitmap.yaml.
Run fsx subsuite with both filestore and bluestore.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
