[2/2] dtc: Make -Idts -Odts preserve property-internal labels

[Jon Loeliger]

So, like, the other day David Gibson mumbled:
> This patch changes -Odts mode output so that labels within property
> values in the input are preserved in the output.  Applied on top of
> the earlier patch to preserve node and property labels in -Odts mode,
> this means that dtc in -Idts -Odts mode will transfer all labels in
> the input to the output.
> 
> Signed-off-by: David Gibson <david at gibson.dropbear.id.au>

Applied.

jdl