net/mlx5: E-Switch, Correct type to u16 for vport_num and int for vport_index

To avoid any ambiguity between vport index and vport number,
rename functions that had vport, to vport_num or vport_index appropriately.

vport_num is u16 hence change mlx5_eswitch_index_to_vport_num() return
type to u16.

vport_index is an int in vport array. Hence change input type of vport
index in mlx5_eswitch_index_to_vport_num() to int.

Correct multiple eswitch representor interfaces use type u16 of
rep->vport as type int vport_index.

Send vport FW commands with correct eswitch u16 vport_num instead
host int vport_index.

Fixes: 5ae51620

 ("net/mlx5: E-Switch, Assign a different position for uplink rep and vport")
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Vu Pham <vuhuong@mellanox.com>
Reviewed-by: Bodong Wang <bodong@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>