[CRIU] Cgroups breakage on ppc64

[Cyrill Gorcunov]

Hi Tycho! In commit 6e33d08045b51 you introduced
struct parasite_dump_cgroup_args which actually
too big for ppc64 machine and we fail here with

gcc -c -O2 -g -Wall -Werror -DCONFIG_PPC64 -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE -fno-strict-aliasing -iquote /home/cyrill/criu/criu/include -iquote /home/cyrill/criu/images -iquote
/home/cyrill/criu/criu/pie -iquote /home/cyrill/criu/criu/arch/ppc64 -iquote /home/cyrill/criu/criu/arch/ppc64/include -iquote /home/cyrill/criu/ -I/usr/include/libnl3 -iquote ppc64 -DCONFIG_PPC64
-D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE parasite-syscall.c -o parasite-syscall.o
parasite-syscall.c: In function ‘parasite_dump_cgroup’:
parasite-syscall.c:1283:2: error: size of unnamed array is negative
  ca = parasite_args(ctl, struct parasite_dump_cgroup_args);
  ^
/home/cyrill/criu/scripts/nmk/scripts/rules.mk:53: recipe for target 'parasite-syscall.o' failed

Because not have enough space in parasite arguments area size ;)
Take a look please once time permit. I think Laurent knows a
way more about ppc specifics. CC'ed.

	Cyrill