[PATCH] -Wundef fixes (hamachi)

All uses of ADDRLEN are comparisons with 64 (it's an address width).
added define to 32 (again, we only care about comparisons with 64)
if not defined.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>