kernel: shim-inet4: mock-up sdu_write() implementation
kernel: shim-inet4: mock-up sdu_write() implementation

autrimpo/rlite,autrimpo/rlite,vmaffione/rlite,vmaffione/rlite,vmaffione/rlite,autrimpo/rlite,vmaffione/rlite,autrimpo/rlite