net: fec: add initial XDP support

net: fec: add initial XDP support

This patch adds the initial XDP support to Freescale driver. It supports
XDP_PASS, XDP_DROP and XDP_REDIRECT actions. Upcoming patches will add
support for XDP_TX and Zero Copy features.

As the patch is rather large, the part of codes to collect the
statistics is separated and will prepare a dedicated patch for that
part.

I just tested with the application of xdpsock.
  -- Native here means running command of "xdpsock -i eth0"
  -- SKB-Mode means running command of "xdpsock -S -i eth0"

The following are the testing result relating to XDP mode:

root@imx8qxpc0mek:~/bpf# ./xdpsock -i eth0
 sock0@eth0:0 rxdrop xdp-drv
                   pps            pkts           1.00
rx                 371347         2717794
tx                 0              0

root@imx8qxpc0mek:~/bpf# ./xdpsock -S -i eth0
 sock0@eth0:0 rxdrop xdp-skb
                   pps            pkts           1.00
rx                 202229         404528
tx                 0              0

root@imx8qxpc0mek:~/bpf# ./xdp2 eth0
proto 0:     496708 pkt/s
proto 0:     505469 pkt/s
proto 0:     505283 pkt/s
proto 0:     505443 pkt/s
proto 0:     505465 pkt/s

root@imx8qxpc0mek:~/bpf# ./xdp2 -S eth0
proto 0:          0 pkt/s
proto 17:     118778 pkt/s
proto 17:     118989 pkt/s
proto 0:          1 pkt/s
proto 17:     118987 pkt/s
proto 0:          0 pkt/s
proto 17:     118943 pkt/s
proto 17:     118976 pkt/s
proto 0:          1 pkt/s
proto 17:     119006 pkt/s
proto 0:          0 pkt/s
proto 17:     119071 pkt/s
proto 17:     119092 pkt/s

Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20221031185350.2045675-1-shenwei.wang@nxp.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>