LU-17088 dom: don't create different size DOM component

LU-17088 dom: don't create different size DOM component

Multiple DOM components are allowed in diffrent mirror but they
must be of the same size, mirror extend should check this restraint.

Fix another glitch in lov_init_composite() where dom_size is used
as a __u64 value but declared as boolean.

Fixes: 44a721b8c1 ("LU-11421 dom: manual OST-to-DOM migration via mirroring")
Signed-off-by: Bobi Jam <bobijam@whamcloud.com>
Change-Id: Ia0d08c697dbeeb3aa8d20d9849226afa06360012
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/52269
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Mikhail Pershin <mpershin@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>