[tlbuild] lcdf-typetools-2.78 -- is hashcode() unsigned, uint32_t, or size_t

[Karl Berry]

    using uint32_t without *explictly* including the header(s) supposed to
    define it make this a but fragile, depending on the fact that these are
    included implicitly

Clearly.  But for the same reason I think it is preferable to avoid
uint32_t in the first place.  That's why I wrote what I did, surmising
that the problem was a conflict between uint32_t and unsigned (why else
use the former).  Anyway ...