socket: calloc expects struct size as second parameter
socket: calloc expects struct size as second parameter

The parameters where accidentally swapped.

Reported-by: Chris Rapier <5f6e6c540dd8ad89021590ec15a29a4c4e206cba@psc.edu>
Signed-off-by: Pablo Neira Ayuso <707d14912bb250caf67dfe0ea4035681fbfc4f56@netfilter.org>

chamaken/libmnl,chamaken/libmnl,greearb/libmnl-ct,greearb/libmnl-ct