net/mlx5: Align mlx5_irq structure

mlx5_irq structure have holes due to incorrect position of fields in it.
Make them naturally align.

pahole output after alignment:
struct mlx5_irq {
        struct atomic_notifier_head nh;                  /*     0    72 */
        /* --- cacheline 1 boundary (64 bytes) was 8 bytes ago --- */
        cpumask_var_t              mask;                 /*    72     8 */
        char                       name[32];             /*    80    32 */
        struct mlx5_irq_pool *     pool;                 /*   112     8 */
        struct kref                kref;                 /*   120     4 */
        u32                        index;                /*   124     4 */
        /* --- cacheline 2 boundary (128 bytes) --- */
        int                        irqn;                 /*   128     4 */

        /* size: 136, cachelines: 3, members: 7 */
        /* padding: 4 */
        /* last cacheline: 8 bytes */

};

Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>