Kernel prepatch 5.15-rc2

The 5.15-rc2 kernel prepatch is out for
testing.

So I've spent a fair amount of this week trying to sort out all the
odd warnings, and I want to particularly thank Guenter Roeck for his
work on tracking where the build failures due to -Werror come from.

Is it done? No. But on the whole I'm feeling fairly good about this
all, even if it has meant that I've been looking at some really odd
and grotty code. Who knew I'd still worry about some odd EISA driver
on alpha, after all these years? A slight change of pace;)