These are all kernel internal interfaces that get copied
around a lot. In most cases, architectures can provide
their own optimized versions, but these generic versions
can work as well.

I have tried to use the most common contents of each
header to allow existing architectures to migrate easily.

Thanks to Remis for suggesting a number of cleanups.

Signed-off-by: Remis Lima Baima
Signed-off-by: Arnd Bergmann