[U-Boot] [PATCH] arc: add stubs for map_physmem() and unmap_physmem()

[Stephen Warren]

On 11/12/2015 02:56 PM, Alexey Brodkin wrote:
> Up until now there was no need in those stubs.
>
> But since following commit compilation of U-Boot on ARC is broken:
> commit 7861204c9af7fec1ea9b41541c272516235a6c93
>      itest: make memory access work under sandbox
>
...
> That's because CMD_ITEST is enabled by default in common/Kconfig and now
> map_physmem()/unmap_physmem() is used there.
>
> So this patch adds missing stubs for ARC.

This looks OK, but rather than cut/pasting this exact same code yet 
another time, why not create e.g. include/io-base.h that contains this, 
and share it amongst all architectures?