davinci: add arch_ioremap() which uses existing static mappings

Add arch-specific ioremap() which uses any existing static mappings in
place of doing a new mapping.  From now on, drivers should always use
ioremap() instead of IO_ADDRESS().

In addition, remove the davinci_[read|write]* macros in favor of using
ioremap.

Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

arch/arm/mach-davinci/include/mach/gpio.h

@@ -15,9 +15,11 @@
 
 #include <linux/io.h>
 #include <asm-generic/gpio.h>
-#include <mach/hardware.h>
+
 #include <mach/irqs.h>
 
+#define DAVINCI_GPIO_BASE 0x01C67000
+
 /*
  * basic gpio routines
  *