bnxt_en: remove set but not used variable 'rx_stats'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/net/ethernet/broadcom/bnxt/bnxt_vfr.c: In function 'bnxt_vf_rep_rx':
drivers/net/ethernet/broadcom/bnxt/bnxt_vfr.c:212:28: warning:
 variable 'rx_stats' set but not used [-Wunused-but-set-variable]
  struct bnxt_vf_rep_stats *rx_stats;
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt_vfr.c

@@ -209,9 +209,7 @@ struct net_device *bnxt_get_vf_rep(struct bnxt *bp, u16 cfa_code)
 void bnxt_vf_rep_rx(struct bnxt *bp, struct sk_buff *skb)
 {
 	struct bnxt_vf_rep *vf_rep = netdev_priv(skb->dev);
-	struct bnxt_vf_rep_stats *rx_stats;
 
-	rx_stats = &vf_rep->rx_stats;
 	vf_rep->rx_stats.bytes += skb->len;
 	vf_rep->rx_stats.packets++;