IMSM: Count arrays per orom

IMSM: Count arrays per orom

Active arrays with IMSM metadata are counted per hba so far.
This is bad due to new functionality of orom shared between multiple
controllers i.e. more arrays can be created than is supported by orom.
This patch changes the way of counting arrays, so the result will be
sum of arrays under every hba supported by specific orom.

Signed-off-by: Pawel Baldysiak <pawel.baldysiak@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>