This is only needed when using SRAM for framebuffer,
and the support for SRAM framebuffer is about to get
removed.

Otherwise we cannot move most of plat/io.h to be a local
iomap.h for mach-omap2.

Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Tony Lindgren <tony@atomide.com>