net/mlx5: Fix atomic_mode enum values

The field atomic_mode is 4 bits wide and therefore can hold values
from 0x0 to 0xf. Remove the unnecessary 20 bit shift that made the values
be incorrect. While that, remove unused enum values.

Fixes: 57cda166 ("net/mlx5: Add DCT command interface")
Signed-off-by: Moni Shoua <monis@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

include/linux/mlx5/driver.h

@@ -163,10 +163,7 @@ enum mlx5_dcbx_oper_mode {
 };
 
 enum mlx5_dct_atomic_mode {
-	MLX5_ATOMIC_MODE_DCT_OFF        = 20,
-	MLX5_ATOMIC_MODE_DCT_NONE       = 0 << MLX5_ATOMIC_MODE_DCT_OFF,
-	MLX5_ATOMIC_MODE_DCT_IB_COMP    = 1 << MLX5_ATOMIC_MODE_DCT_OFF,
-	MLX5_ATOMIC_MODE_DCT_CX         = 2 << MLX5_ATOMIC_MODE_DCT_OFF,
+	MLX5_ATOMIC_MODE_DCT_CX         = 2,
 };
 
 enum {