powerpc/pci: Clean up direct access to sysdata by indirect ops

We shouldn't directly access sysdata to get the pci_controller.  Instead
use pci_bus_to_host() for this purpose.  In the future we might have
sysdata be a device_node to match ppc64 and unify the code between ppc32
& ppc64.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/sysdev/indirect_pci.c

@@ -24,7 +24,7 @@ static int
 indirect_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
 		     int len, u32 *val)
 {
-	struct pci_controller *hose = bus->sysdata;
+	struct pci_controller *hose = pci_bus_to_host(bus);
 	volatile void __iomem *cfg_data;
 	u8 cfg_type = 0;
 	u32 bus_no, reg;
@@ -82,7 +82,7 @@ static int
 indirect_write_config(struct pci_bus *bus, unsigned int devfn, int offset,
 		      int len, u32 val)
 {
-	struct pci_controller *hose = bus->sysdata;
+	struct pci_controller *hose = pci_bus_to_host(bus);
 	volatile void __iomem *cfg_data;
 	u8 cfg_type = 0;
 	u32 bus_no, reg;