If you're using externalsrc, it's very likely that you're going to want
to examine the intermediate build results even if the recipe builds
successfully; therefore you won't want rm_work to delete those.
(From OE-Core rev: c0867a425166086624bcffa231a1497291f860cb)
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>