If net_send_data() returns 0, then the buffer was sent ok
and the sending device driver has already freed the buffer.
If net_send_data() returns <0, then the buffer sending failed
and the caller can either try to fix the issue and re-send the
buffer, or the caller can unref the buffer. Normally caller
should unref the buffer in this case as there is not much that
can be done here.
Change-Id: I39d7b22bbb78a9c16fd037f3a066797e455c31fd
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
d41325edee