[WATCHDOG] i8xx_tco remove pci_find_device.

Use refcounting for pci device obtaining.
Use PCI_DEVICE macro.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: Andrew Morton <akpm@osdl.org>