net/mlx5e: Remove MLX5E_TEST_BIT macro

MLX5E_TEST_BIT macro is the same as the already existent test_bit,
remove it and replace all usages.

Signed-off-by: Gal Pressman <galp@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>