more trivial signedness fixes in drivers

drivers/acpi/toshiba_acpi.c

drivers/ata/ata_piix.c

drivers/ata/sata_via.c

drivers/atm/firestream.c

drivers/block/cciss.c

drivers/hid/hid-input.c

drivers/isdn/hisax/hfc_2bds0.c

drivers/isdn/hisax/nj_s.c

drivers/net/tulip/tulip_core.c

drivers/pci/pci.c

sound/usb/usbaudio.c