sk: Pre-read sock packets into buffer

 criu/sk-queue.c | 33 ++++++++++++---------------------
 1 file changed, 12 insertions(+), 21 deletions(-)

In order to prepare for the use of sockets to transfer the image files
lseek calls needs to be removed. For sk-queue, we now read the packet
data at the same time than the header. This has the disadvantage to
consume more memory between the image read and the packets restore, but
should hopefully be affordable.

Signed-off-by: Rodrigo Bruno <rbruno@gsd.inesc-id.pt>
Signed-off-by: Katerina Koukiou <k.koukiou@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>