nvmem: core: Use kobj_to_dev() instead of container_of()

Use kobj_to_dev() instead of container_of()

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200917134437.16637-3-srinivas.kandagatla@linaro.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>