cxgb4: remove redundant assignment to vlan_cmd.dropnovlan_fm

A recent commit updated vlan_cmd.dropnovlan_fm but failed to remove
the older assignment.  Fix this by removing the former redundant
assignment.

Detected by CoverityScan, CID#1473290 ("Unused value")

Fixes: a89cdd8e7c74 ("cxgb4: impose mandatory VLAN usage when non-zero TAG ID")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/t4_hw.c

@@ -10209,7 +10209,6 @@ int t4_set_vlan_acl(struct adapter *adap, unsigned int mbox, unsigned int vf,
 					 FW_ACL_VLAN_CMD_VFN_V(vf));
 	vlan_cmd.en_to_len16 = cpu_to_be32(enable | FW_LEN16(vlan_cmd));
 	/* Drop all packets that donot match vlan id */
-	vlan_cmd.dropnovlan_fm = FW_ACL_VLAN_CMD_FM_F;
 	vlan_cmd.dropnovlan_fm = (enable
 				  ? (FW_ACL_VLAN_CMD_DROPNOVLAN_F |
 				     FW_ACL_VLAN_CMD_FM_F) : 0);