rocker: Simplify the calculation of variables

Fix the following coccicheck warnings:

./drivers/net/ethernet/rocker/rocker_ofdpa.c:926:34-36: WARNING !A || A
&& B is equivalent to !A || B.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Zhong <abaci-bugfix@linux.alibaba.com>
Link: https://lore.kernel.org/r/1611648783-3916-1-git-send-email-abaci-bugfix@linux.alibaba.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/rocker/rocker_ofdpa.c

@@ -923,7 +923,7 @@ static int ofdpa_flow_tbl_bridge(struct ofdpa_port *ofdpa_port,
 	struct ofdpa_flow_tbl_entry *entry;
 	u32 priority;
 	bool vlan_bridging = !!vlan_id;
-	bool dflt = !eth_dst || (eth_dst && eth_dst_mask);
+	bool dflt = !eth_dst || eth_dst_mask;
 	bool wild = false;
 
 	entry = kzalloc(sizeof(*entry), GFP_ATOMIC);