sctp: missing set src and dest port while lookup output route

While lookup the output route, we do not set the src and dest
port. This will cause we got a wrong route if we had set the
outbund transport to IPsec with src or dst port.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>