Crash in CIPSO_V4_TAG_LOCAL handling

DaveM asked that this goes direct to the list so ...

Looking at some static code analyser output and the results seem valid on
this one:

ip_options_compile called with skb = NULL and an IPOPT_CIPSO option calls
into cipso_v4_validate, which if the option is CIPSO_V4_TAG_LOCAL then
dereferences skb->dev and explodes.

All the other cases appear to correctly avoid or check it versus NULL

Alan