net/mlx5: E-Switch, rename bond update function to be reused

The vport bond update function is really updating the vport metadata
and there is no direct relation to bond. Rename the function
to vport metadata update to be used a followup commit.
This commit doesn't change any functionality.

Signed-off-by: Roi Dayan <roid@nvidia.com>
Reviewed-by: Maor Dickman <maord@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>