We missed restore problems with multiple semaphores in one array
with vzt-cpt, enhance the test to catch it.

The problem was the change of 'struct sem' size which lead to wrong
memcpy of sem_array->sem_base in our kernel checkpointing.
Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>