PCI: mvebu: Fix potential issue in range parsing

commit 4f4bde1d upstream.

The second parameter of of_read_number() is not the index, but a size.  As
it happens, in this case it may work just fine because of the conversion to
u32 and the favorable endianness on this architecture.

Fixes: 11be6547 ("PCI: mvebu: Adapt to the new device tree layout")
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

drivers/pci/host/pci-mvebu.c

@@ -749,7 +749,7 @@ static int mvebu_get_tgt_attr(struct device_node *np, int devfn,
 
 	for (i = 0; i < nranges; i++) {
 		u32 flags = of_read_number(range, 1);
-		u32 slot = of_read_number(range, 2);
+		u32 slot = of_read_number(range + 1, 1);
 		u64 cpuaddr = of_read_number(range + na, pna);
 		unsigned long rtype;