Documentation PCI: Reformat RMW ops documentation

Documentation PCI: Reformat RMW ops documentation

Extract the list of RMW protected PCIe Capability registers into a
bullet list to make them easier to pick up on a glance. An upcoming
change is going to add one more register among them so it will be much
cleaner to have them as bullets.

Link: https://lore.kernel.org/r/20241018144755.7875-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>