linux-yocto: copy defconfig

The defconfig has been copied by oe-framework. Since last (2013-03)
oe layer update, it is not coopied into the build directory. The
cause is unknown. As long as it does not work, it is copied here.

Signed-off-by: Mario Schuknecht <schuknecht@dresearch-fe.de>
hydraip-image: disable iscsi-target

Disable temporarily iscsi-target because of compile errors.

Signed-off-by: Mario Schuknecht <schuknecht@dresearch-fe.de>