IB/mlx5: Fix coverity warning

Fix covertiy warning of passing "&flow_attr" to function
"create_flow_rule" which uses it as an array.

In addition pass flow attributes argument as const.
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/mlx5/main.c

@@ -1437,7 +1437,7 @@ static bool outer_header_zero(u32 *match_criteria)
 }
 
 static int parse_flow_attr(u32 *match_c, u32 *match_v,
-			   union ib_flow_spec *ib_spec)
+			   const union ib_flow_spec *ib_spec)
 {
 	void *outer_headers_c = MLX5_ADDR_OF(fte_match_param, match_c,
 					     outer_headers);
@@ -1605,7 +1605,7 @@ static bool flow_is_multicast_only(struct ib_flow_attr *ib_attr)
 	       is_multicast_ether_addr(eth_spec->val.dst_mac);
 }
 
-static bool is_valid_attr(struct ib_flow_attr *flow_attr)
+static bool is_valid_attr(const struct ib_flow_attr *flow_attr)
 {
 	union ib_flow_spec *ib_spec = (union ib_flow_spec *)(flow_attr + 1);
 	bool has_ipv4_spec = false;
@@ -1729,13 +1729,13 @@ static struct mlx5_ib_flow_prio *get_flow_table(struct mlx5_ib_dev *dev,
 
 static struct mlx5_ib_flow_handler *create_flow_rule(struct mlx5_ib_dev *dev,
 						     struct mlx5_ib_flow_prio *ft_prio,
-						     struct ib_flow_attr *flow_attr,
+						     const struct ib_flow_attr *flow_attr,
 						     struct mlx5_flow_destination *dst)
 {
 	struct mlx5_flow_table	*ft = ft_prio->flow_table;
 	struct mlx5_ib_flow_handler *handler;
 	struct mlx5_flow_spec *spec;
-	void *ib_flow = flow_attr + 1;
+	const void *ib_flow = (const void *)flow_attr + sizeof(*flow_attr);
 	unsigned int spec_index;
 	u32 action;
 	int err = 0;