bmp: bug fix of peer bgp ID in BMP Message

Ryu BGP sets self-BGP ID as Peer BGP ID in BMP Message.

Signed-off-by: Yuji Oshima <yuji.oshima0x3fd@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
packet lib: don't crash with bogus ospf packet

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>