LU-13645 ldlm: extra checks for DOM locks

LU-13645 ldlm: extra checks for DOM locks

a couple of checks are added:
- only DOM lock can be a group lock;
- DOM bit must be the only mandatory one, or optional;

Signed-off-by: Vitaly Fertman <c17818@cray.com>
HPE-bug-id: LUS-8987
Change-Id: Iaf7a14a66eb0f125d2f6f7d06f5de0add387e101
Reviewed-on: https://review.whamcloud.com/39878
Reviewed-by: Mike Pershin <mpershin@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>