net/mlx5: clean function declarations in eswitch.c up

We get 2 warnings when building kernel with W=1:
drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c:463:5: warning: no previous prototype for 'esw_offloads_init' [-Wmissing-prototypes]
drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c:521:6: warning: no previous prototype for 'esw_offloads_cleanup' [-Wmissing-prototypes]

In fact, both functions are declared in
drivers/net/ethernet/mellanox/mlx5/core/eswitch.c,but should be
declared in a header file, thus can be recognized in other file.

So this patch moves the declarations into
drivers/net/ethernet/mellanox/mlx5/core/eswitch.h
Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx5/core/eswitch.c

@@ -81,9 +81,6 @@ enum {
 			    MC_ADDR_CHANGE | \
 			    PROMISC_CHANGE)
 
-int esw_offloads_init(struct mlx5_eswitch *esw, int nvports);
-void esw_offloads_cleanup(struct mlx5_eswitch *esw, int nvports);
-
 static int arm_vport_context_events_cmd(struct mlx5_core_dev *dev, u16 vport,
 					u32 events_mask)
 {

drivers/net/ethernet/mellanox/mlx5/core/eswitch.h

@@ -209,6 +209,9 @@ struct mlx5_eswitch {
 	int                     mode;
 };
 
+void esw_offloads_cleanup(struct mlx5_eswitch *esw, int nvports);
+int esw_offloads_init(struct mlx5_eswitch *esw, int nvports);
+
 /* E-Switch API */
 int mlx5_eswitch_init(struct mlx5_core_dev *dev);
 void mlx5_eswitch_cleanup(struct mlx5_eswitch *esw);