[1/2] libfdt: Rework fdt_next_node()

[Jon Loeliger]

> Currently fdt_next_node() will find the next node in the blob
> regardless of whether it is above, below or at the same level in the
> tree as the starting node - the depth parameter is updated to indicate
> which is the case.  When a depth parameter is supplied, this patch
> makes it instead terminate immediately when it finds the END_NODE tag
> for a node at depth 0.  In this case it returns the offset immediately
> past the END_NODE tag.
> 
> This has a couple of advantages.  First, this slightly simplifies
> fdt_subnode_offset(), which no longer needs to explicitly check that
> fdt_next_node()'s iteration hasn't left the starting node.  Second,
> this allows fdt_next_node() to be used to implement
> _fdt_node_end_offset() considerably simplifying the latter function.
> 
> The other users of fdt_next_node() either don't need to iterate out of
> the starting node, or don't pass a depth parameter at all.  Any
> callers that really need to iterate out of the starting node, but keep
> tracking depth can do so by biasing the initial depth value.
> 
> This is a semantic change, but I think it's very unlikely to break any
> existing library users.
> 
> Signed-off-by: David Gibson <david at gibson.dropbear.id.au>

Applied.

Thanks,
jdl