netdev-dpdk: fix ingress_policer leak on error path

Fix memory leak by freeing the policer if rte_meter_srtcm_config fails.

Fixes: 9509913aa7 ("netdev-dpdk.c: Add ingress-policing functionality.")
Signed-off-by: zhangliping <zhangliping02@baidu.com>
Signed-off-by: Ian Stokes <ian.stokes@intel.com>

lib/netdev-dpdk.c

@@ -2436,6 +2436,7 @@ netdev_dpdk_policer_construct(uint32_t rate, uint32_t burst)
                                     &policer->app_srtcm_params);
     if (err) {
         VLOG_ERR("Could not create rte meter for ingress policer");
+        free(policer);
         return NULL;
     }