staging: fsl-dpaa2/eth: Merge header files

File net.h contains definitions that are exclusively used by
the key generator/classification API. Merge its contents with
dpkg.h in order to reduce the number of private headers.
Signed-off-by: Ioana Radulescu <ruxandra.radulescu@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>