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/clock2430.c b/arch/arm/mach-omap2/clock2430.c
index d87bc9c..0caf792 100644
--- a/arch/arm/mach-omap2/clock2430.c
+++ b/arch/arm/mach-omap2/clock2430.c
@@ -23,6 +23,7 @@
 
 #include <plat/clock.h>
 
+#include "iomap.h"
 #include "clock.h"
 #include "clock2xxx.h"
 #include "cm2xxx_3xxx.h"