Merge tag 'rust_io-7.1-rc1' into driver-core-next

Register abstraction and I/O infrastructure improvements

Introduce the register!() macro to define type-safe I/O register
accesses. Refactor the IoCapable trait into a functional trait, which
simplifies I/O backends and removes the need for overloaded Io methods.

This is a stable tag for other trees to merge.

Signed-off-by: Danilo Krummrich <dakr@kernel.org>