net: netsec: Add metadata support for xdp mode

net: netsec: Add metadata support for xdp mode

Set metadata size building the skb from xdp_buff in netsec driver.
netsec driver sets xdp headroom to NETSEC_RXBUF_HEADROOM:

NETSEC_RXBUF_HEADROOM max(XDP_PACKET_HEADROOM, NET_SKB_PAD) + NET_IP_ALIGN

so the headroom is large enough to contain xdp_frame and xdp metadata.
Please note this patch is just compiled tested.

Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://patch.msgid.link/20250318-mvneta-xdp-meta-v2-3-b6075778f61f@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>