Kernel prepatch 6.1-rc6

The 6.1-rc6 kernel prepatch is out fortesting.

I'm still waffling about whether there will be an rc8 or not, leaning a bit towards it happening. We'll see - it will make the 6.2 merge window leak into the holidays, but maybe that's fine and just makes people make sure they have everything lined up and ready *before* the merge window opens, the way things _should_ work.