lwip: nd6: Handle incorrect ICMP option length in RA
lwip: nd6: Handle incorrect ICMP option length in RA

Upstream commit: d98e25a783a5b1ee9813b8337232384660fd545f

ambrop72/aprinter,johnkingsley/aprinter,ambrop72/aprinter,johnkingsley/aprinter,ambrop72/aprinter,johnkingsley/aprinter,ambrop72/aprinter,johnkingsley/aprinter,ambrop72/aprinter,ambrop72/aprinter,johnkingsley/aprinter,ambrop72/aprinter,johnkingsley/aprinter,johnkingsley/aprinter