iotests: blacklist bochs and cloop for 205 and 208

Blacklist these formats, as they don't support image creation, as they
say:
    > ./qemu-img create -f bochs x 1m
    qemu-img: x: Format driver 'bochs' does not support image creation

    > ./qemu-img create -f cloop x 1m
    qemu-img: x: Format driver 'cloop' does not support image creation

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2 files changed