vdpa_sim: advertise VIRTIO_NET_F_MTU

We've already reported maximum mtu via config space, so let's
advertise the feature.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NGautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-17-gdawar@xilinx.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

drivers/vdpa/vdpa_sim/vdpa_sim_net.c

@@ -26,7 +26,8 @@
 #define DRV_LICENSE  "GPL v2"
 
 #define VDPASIM_NET_FEATURES	(VDPASIM_FEATURES | \
-				 (1ULL << VIRTIO_NET_F_MAC))
+				 (1ULL << VIRTIO_NET_F_MAC) | \
+				 (1ULL << VIRTIO_NET_F_MTU))
 
 #define VDPASIM_NET_VQ_NUM	2