x86/PCI: Fix Broadcom CNB20LE unintended sign extension

In the expression "word1 << 16", word1 starts as u16, but is promoted to
a signed int, then sign-extended to resource_size_t, which is probably
not what was intended.  Cast to resource_size_t to avoid the sign
extension.

Found by Coverity (CID 138749, 138750).
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

arch/x86/pci/broadcom_bus.c

@@ -60,8 +60,8 @@ static void __init cnb20le_res(u8 bus, u8 slot, u8 func)
 	word1 = read_pci_config_16(bus, slot, func, 0xc4);
 	word2 = read_pci_config_16(bus, slot, func, 0xc6);
 	if (word1 != word2) {
-		res.start = (word1 << 16) | 0x0000;
-		res.end   = (word2 << 16) | 0xffff;
+		res.start = ((resource_size_t) word1 << 16) | 0x0000;
+		res.end   = ((resource_size_t) word2 << 16) | 0xffff;
 		res.flags = IORESOURCE_MEM | IORESOURCE_PREFETCH;
 		update_res(info, res.start, res.end, res.flags, 0);
 	}