net/mlx5: Address static checker warnings on non-constant initializers

Address these sparse warnings on drivers/net/ethernet/mellanox/mlx5

[..]/core/diag/fs_tracepoint.c:99:53: warning: non-constant initializer for static object
[..]/core/diag/fs_tracepoint.c:102:53: warning: non-constant initializer for static object

etc

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>