net/mlx5: Update SRIOV enable/disable to handle EC/VFs

Previously on the embedded CPU platform SRIOV was never enabled/disabled
via mlx5_core_sriov_configure. Host VF updates are provided by an event
handler. Now in the disable flow it must be known if this is a disable
due to driver unload or SRIOV detach, or if the user updated the number
of VFs. If due to change in the number of VFs only wait for the pages of
ECVFs.

Signed-off-by: Daniel Jurgens <danielj@nvidia.com>
Reviewed-by: William Tu <witu@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>