Merge series from Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>: Use container_of_const(), which is preferred over container_of(), when the argument 'ptr' and returned pointer are already const, for better code safety and readability. Some drivers already have const everywhere, so container_of_const can be directly used. In few other drivers, the final pointer can be constified that way.