[POWERPC] iseries: eliminate a couple of warnings

Copy and paste bug in io.h
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

include/asm-powerpc/io.h

@@ -68,8 +68,8 @@ extern unsigned long pci_io_base;
  * for older code.
  */
 #define insb(port, buf, ns)	_insb((u8 __iomem *)((port)+pci_io_base), (buf), (ns))
-#define insw(port, buf, ns)	_insw_ns((u8 __iomem *)((port)+pci_io_base), (buf), (ns))
-#define insl(port, buf, nl)	_insl_ns((u8 __iomem *)((port)+pci_io_base), (buf), (nl))
+#define insw(port, buf, ns)	_insw_ns((u16 __iomem *)((port)+pci_io_base), (buf), (ns))
+#define insl(port, buf, nl)	_insl_ns((u32 __iomem *)((port)+pci_io_base), (buf), (nl))
 
 #else