[Bro-Dev] Bro fails on clean checkout

[Siwek, Jonathan Luke]

> I get the following errors when building:
> /Users/katrina/test-bro/bro/src/IP.cc: In function ‘VectorVal* BuildOptionsVal(const u_char*, int)’:
> /Users/katrina/test-bro/bro/src/IP.cc:46: error: invalid use of incomplete type ‘const struct ip6_opt’
> /Users/katrina/test-bro/bro/src/IP.cc:44: error: forward declaration of ‘const struct ip6_opt’

I get the ip6_opt type from my <netinet/ip6.h>.  On OS X 10.7.3:

/* IPv6 options: common part */
struct ip6_opt {
    u_int8_t ip6o_type;
    u_int8_t ip6o_len;
} __attribute__((__packed__));

If that's not a standard type, we might add a configure-time check to see if it exists and define it if not.  Or we might just always define our own type.  I'll look more into what standard ways of defining the IPv6 header structures are.

+Jon