It doesn't need to include i2c.h, because a forward declaration of
struct i2c_adapter is perfectly sufficient. And it can be inside
#ifdef __KERNEL__ along with the kernel-internal structure definition.
Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!