net/mlx5: Rename mlx5_sf_dev_remove

Mlx5 has two functions with the same name mlx5_sf_dev_remove. Both are
static, in different files, so no compilation or logical issue, but it
makes it hard to follow the code and some traces even can get both as
one leads to the other [1]. Rename one to mlx5_sf_dev_remove_aux() as it
actually removes the auxiliary device of the SF.

[1]
 mlx5_sf_dev_remove+0x2a/0x70 [mlx5_core]
 auxiliary_bus_remove+0x18/0x30
 device_release_driver_internal+0x199/0x200
 bus_remove_device+0xd7/0x140
 device_del+0x153/0x3d0
 ? process_one_work+0x16a/0x4b0
 mlx5_sf_dev_remove+0x2e/0x90 [mlx5_core]
 mlx5_sf_dev_table_destroy+0xa0/0x100 [mlx5_core]

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>