zdtm: check pre-dump of shared memory

[root@fc24 criu]# python test/zdtm.py run -t zdtm/transition/shmem  --pre 3
=== Run 1/1 ================

======================== Run zdtm/transition/shmem in h ========================
cc -g -O2 -Wall -Werror -fno-strict-aliasing  -iquote ../lib/arch/x86/include -I../lib   shmem.c ../lib/libzdtmtst.a ../lib/libzdtmtst.a -o shmem
Start test
./shmem --pidfile=shmem.pid --outfile=shmem.out
Run criu pre-dump
Run criu pre-dump
Run criu pre-dump
Run criu dump
Run criu restore
Send the 15 signal to  33
Wait for zdtm/transition/shmem(33) to die for 0.100000
Test output: ================================
15:12:25.444:    33: FAIL: shmem.c:70: checksum mismatch: ea71000 109c9000

Cc: Eugene Batalov <eabatalov89@gmail.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>