ARM: OMAP2+: Move most of plat/io.h into local iomap.h

There's no need to have these defines in plat/io.h.

Note that we now need to ifdef omap_read/write calls
as they will be available for omap1 only.

While at it, clean up the includes to group them like
they typically are grouped.

Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/mach-omap2/emu.c b/arch/arm/mach-omap2/emu.c
index 9c442e2..28d639f8 100644
--- a/arch/arm/mach-omap2/emu.c
+++ b/arch/arm/mach-omap2/emu.c
@@ -21,6 +21,8 @@
 #include <linux/clk.h>
 #include <linux/err.h>
 
+#include "iomap.h"
+
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Alexander Shishkin");