LU-13939 mgs: warn if nid was not processed during replace_nids

LU-13939 mgs: warn if nid was not processed during replace_nids

process_command() trying to add configuration for each uuid from
list and do not show any message if record_add_uuid() fails. This
can lead to misunderstanding during configuration.

Add warning message if nid can not be added.

Change-Id: Id0a7216daf3eb7e1b8f94eaebd42624b309049d0
hpe-bug-id: LUS-2653
Signed-off-by: Artem Blagodarenko <artem.blagodarenko@hpe.com>
Reviewed-on: https://es-gerrit.dev.cray.com/157402
Reviewed-by: Vladimir Saveliev <c17830@cray.com>
Reviewed-by: Alexander Boyko <c17825@cray.com>
Tested-by: Alexander Lezhoev <c17454@cray.com>
Reviewed-on: https://review.whamcloud.com/39795
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Alexander Boyko <alexander.boyko@hpe.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>