ga_channel_listen_accept() is currently hard-coded to support only
AF_UNIX because the struct sockaddr_un type is used. This function
should work with any address family.
Drop the sockaddr since the client address is unused and is an optional
argument to accept(2).
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>