bus/dpaa: support shared MAC

bus/dpaa: support shared MAC

A shared MAC interface is an interface which can be used
by both kernel and userspace based on classification configuration
It is defined in dts with the compatible string
"fsl,dpa-ethernet-shared" which bpool will be seeded by the dpdk
partition and configured as a netdev by the dpaa Linux eth driver.
User space buffers from the bpool will be kmapped by the kernel.

Signed-off-by: Radu Bulie <radu-andrei.bulie@nxp.com>
Signed-off-by: Jun Yang <jun.yang@nxp.com>
Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
Acked-by: Hemant Agrawal <hemant.agrawal@nxp.com>