Remove all init functions that do nothing, and provide a `NULL` to
*DEVICE*DEFINE* macros.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Add a new reset driver for GD32 platforms. This driver controls the
reset registers from the RCU peripheral. It can be used to restore
peripherals to their initial state when initializing a device.
Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>