PCI: Set resource size directly in adjust_bridge_window()

Change adjust_bridge_window() to set resource size directly instead of
using additional resource lists.

Because additional resource lists are optional resources, any algorithm
that requires guaranteed allocation that uses them cannot be guaranteed to
work.

Remove the resource from add_list, as a zero-sized additional resource is
redundant.

Update comment in pci_bus_distribute_available_resources() to reflect the
above changes.

Link: https://lore.kernel.org/r/PSXP216MB04386BA48874B56BC5CB0292803C0@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM


Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>