IB/mlx5: Remove unnecessary return statement

There is no reason to call return at the end of function which returns
void. Remove this unnecessary statement.

Link: https://lore.kernel.org/r/20191002122517.17721-3-leon@kernel.org


Signed-off-by: Erez Alfasi <ereza@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>