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>
diff --git a/arch/arm/mach-davinci/devices.c b/arch/arm/mach-davinci/devices.c
index 808633f..3ea6d47 100644
--- a/arch/arm/mach-davinci/devices.c
+++ b/arch/arm/mach-davinci/devices.c
@@ -22,6 +22,8 @@
 #include <mach/i2c.h>
 #include <mach/irqs.h>
 
+#define DAVINCI_I2C_BASE	     0x01C21000
+
 static struct resource i2c_resources[] = {
 	{
 		.start		= DAVINCI_I2C_BASE,