In preparation to make kobject element in struct device_node optional,
provide and use a macro to return the kobject pointer. The only user
outside the DT core is the driver core.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Tested-by: Nicolas Pitre <nico@linaro.org> Reviewed-by: Frank Rowand <frowand.list@gmail.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Rob Herring <robh@kernel.org>