ACPI: pci_link: simplify list of link devices

We don't need a struct containing a count and a list_head; a simple
list_head is sufficient.  The list iterators handle empty lists
fine.

Furthermore, we don't need to check for null list entries because we
only add non-null entries.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --cc drivers/acpi/pci_link.c
Simple merge