mdmon: ensure Unix domain socket is created with safe permissions.

In the unlikely case that mdmon is started with an overly
permissive umask, we don't want to risk giving away world acccess.

All other "mkdir" and  "O_CREAT" calls in mdmon and mdadm set
a suitably restrictive permission mask.  'bind' don't take an
explicit mask so it needs an implicit one.

Reported-by: Vincent Berg <vberg@ioactive.com>
Signed-off-by: NeilBrown <neilb@suse.de>
IMSM: Add warning message when assemble spanned container

Due to several changes in code assemble with disks
spanned between different controllers can be obtained
in some cases. After IMSM container will be assembled, check HBA of
disks, and print proper warning if mismatch is detected.

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