[ARM] Add a common typesafe __io implementation

As Al did for Versatile in 2ad4f86b60b649fd7428265c08d73a3bd360c81b,
add a typesafe __io implementation for platforms to use.  Convert
platforms to use this new simple typesafe implementation.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-davinci/include/mach/io.h b/arch/arm/mach-davinci/include/mach/io.h
index b78ee91..a48795f 100644
--- a/arch/arm/mach-davinci/include/mach/io.h
+++ b/arch/arm/mach-davinci/include/mach/io.h
@@ -29,8 +29,7 @@
  * We don't actually have real ISA nor PCI buses, but there is so many
  * drivers out there that might just work if we fake them...
  */
-#define PCIO_BASE               0
-#define __io(a)			((void __iomem *)(PCIO_BASE + (a)))
+#define __io(a)			__typesafe_io(a)
 #define __mem_pci(a)		(a)
 #define __mem_isa(a)		(a)