These are only three left in ipc_kern_table which we haven't
checkpointed yet, I'm not sure if somebody really uses them
except criu, but to be consistent, beter not to change them
while c/r.

v3: do one sysctl_op for all xxx_next_id(as sysctl_op is quiet slow)
v4: do only one sysctl_op in ipc_sysctl_req
v5: do msg*_default only if have /proc/sys/fs/mqueue same as other
ones from fs/mqueue
Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>