Add the pdelay mac address to the same socket,
it means that one socket has two multicast addr,
E2E and P2P. During recv the wrpc function check
both mac addresses. Send function uses the E2E or
P2P mac addr depending on the msg to be sent.

[changed by Alessandro: create one socket only,
according to Kconfig settings]
Signed-off-by: C.Prados <c.prados@gsi.de>