PCI: switchtec: Use normal comment style

Use normal comment style '/* */' for device ID description.

Link: https://lore.kernel.org/r/20230624000003.2315364-2-kelvin.cao@microchip.com
Signed-off-by: Kelvin Cao <kelvin.cao@microchip.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>