lsm: Postpone lsm_profile vs kerndat checks

We need to keep the host LSM mode on kerndat (next patches),
at the same time the --lsm-profile option needs to correspond
to it.

So split the option handling into two parts -- first keep it
as is, next -- check for kerndat correspondance.

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>