net: ethernet: stmicro: Remove duplicate struct declaration

struct stmmac_safety_stats is declared twice. One has been
declared at 29th line. Remove the duplicate.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/hwif.h

@@ -280,7 +280,6 @@ struct stmmac_dma_ops {
 struct mac_device_info;
 struct net_device;
 struct rgmii_adv;
-struct stmmac_safety_stats;
 struct stmmac_tc_entry;
 struct stmmac_pps_cfg;
 struct stmmac_rss;