dts: gen_defines: generate `_ORD_STR_SORTABLE`

Generate a zero padded variant of `_ORD` that is suitable for use in
linker scripts with the `SORT` property, so that `6` is correctly placed
before `24`, and so on.

Signed-off-by: Jordan Yates <jordan.yates@data61.csiro.au>
2 files changed