net/mlx5e: E-Switch: move debug print of adding mac to correct place

Move the debug print inside the if clause that actually does the change.

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