[SCTP]: Handle the wildcard ADD-IP Address parameter

The Address Parameter in the parameter list of the ASCONF chunk
may be a wildcard address.  In this case special processing
is required.  For the 'add' case, the source IP of the packet is
added.  In the 'del' case, all addresses except the source IP
of packet are removed. In the "mark primary" case, the source
address is marked as primary.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>