of: move kobj_to_device_node() into dynamic.c

The only user of kobj_to_device_node() is in dynamic.c, so move it
there. This avoids having to make it conditional once kobject is
configurable.

Change-Id: I5bab9af9d6ebda3aff5359e5aba3ca2eccca493e
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>
Git-Commit: 4c2bb57400394e4ec631a42dcf637e925db6202e
Git-Repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Patrick Daly <pdaly@codeaurora.org>