Monitor: skip array if error getting size

Monitor: skip array if error getting size

load_super tries to load container first anyway but if it fails
eg. after physically removing a disk
then it tries to read metadata from container device.
This will always fail and print confusing errors.
So use load_container instead of load_super on container.

On failure to read metadata we should skip this array.
It will be dealt with the next time round.

Signed-off-by: Anna Czarnowska <anna.czarnowska@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>