ssb: trivial: use u8 for chip_rev (it's mask is 0xF)

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/ssb/scan.c b/drivers/ssb/scan.c
index 29884c0..7dca719 100644
--- a/drivers/ssb/scan.c
+++ b/drivers/ssb/scan.c
@@ -307,7 +307,7 @@
 	} else {
 		if (bus->bustype == SSB_BUSTYPE_PCI) {
 			bus->chip_id = pcidev_to_chipid(bus->host_pci);
-			pci_read_config_word(bus->host_pci, PCI_REVISION_ID,
+			pci_read_config_byte(bus->host_pci, PCI_REVISION_ID,
 					     &bus->chip_rev);
 			bus->chip_package = 0;
 		} else {