devtool: extract: copy kernel config to srctree
This makes the correct kernel config to be used when building kernel
from srctree (extrernalsrc). If no kernel config is present in the
builddir 'do_configure' task copies .config from the srctree.
(From OE-Core master rev:
3b516332e038a587685f6e0c14a7f04990bdd6cc)
Signed-off-by: Markus Lehtonen <markus.lehtonen@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
