netdev-dpdk: Don't set rx mq mode for net_virtio.

Since DPDK 18.11.6, it is not allowed to set any RX mq mode for virtio
driver.

Signed-off-by: Jaime Caamaño Ruiz <jcaamano@suse.com>
Acked-by: Flavio Leitner <fbl@sysclose.org>
Signed-off-by: Ian Stokes <ian.stokes@intel.com>

NEWS

@@ -1,5 +1,7 @@
 v2.11.5 - xx xxx xxxx
 ---------------------
+   - DPDK
+     * Fixed support of 'net_virtio' devices.
 
 v2.11.4 - 30 Jul 2020
 ---------------------

lib/netdev-dpdk.c

@@ -162,7 +162,6 @@ typedef uint16_t dpdk_port_t;
 
 static const struct rte_eth_conf port_conf = {
     .rxmode = {
-        .mq_mode = ETH_MQ_RX_RSS,
         .split_hdr_size = 0,
         .offloads = 0,
     },
@@ -915,6 +914,14 @@ dpdk_eth_dev_port_config(struct netdev_dpdk *dev, int n_rxq, int n_txq)
 
     rte_eth_dev_info_get(dev->port_id, &info);
 
+    /* As of DPDK 18.11.6, it is not allowed to set a mq_mode for
+     * virtio PMD driver. */
+    if (!strcmp(info.driver_name, "net_virtio")) {
+        conf.rxmode.mq_mode = ETH_MQ_RX_NONE;
+    } else {
+        conf.rxmode.mq_mode = ETH_MQ_RX_RSS;
+    }
+
     /* As of DPDK 17.11.1 a few PMDs require to explicitly enable
      * scatter to support jumbo RX.
      * Setting scatter for the device is done after checking for