Re: [dtc] Fix flat_dt_property structure

So, like, the other day David Gibson mumbled:

The structure in flat_dt.h defining the layout of a proprety within
the flat device tree is incorrect.  It has the offset to the
property's name, then the length when in fact (according to
booting-without-of.txt and the output of dtc) then length should come
first, followed by the name offset.

In fact, this structure is never used so the mistake doesn't break
anything, but it should still be fixed to avoid misleading people.

Signed-off-by: David Gibson <redacted>

Applied.  Thanks.

jdl