net/mlx5: hw counters: Remove mlx5_fc_create_ex

It no longer serves any purpose and is identical to mlx5_fc_create upon
which it was originally based of.

Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20241001103709.58127-7-tariqt@nvidia.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>