drop memory-hotplug on superH

Hi,

After talking to Adrian Glaubitz about superH and memory-hotplug, he mentioned
that currently superH runs only on 32bits (there was a 64bit version but no is
longer supported?).
The thing is that since the below commit

   commit 7ec58a2b941ed88986694d037e38012738323171
   Author: David Hildenbrand <[email protected]>
   Date:   Fri Nov 5 13:44:28 2021 -0700

       mm/memory_hotplug: restrict CONFIG_MEMORY_HOTPLUG to 64 bit



we no longer support memory-hotplug on 32bit platforms, so let us drop the
memory-hotplug code for superH because it is a no-op at the moment.
If there is ever a 64bit platform again, we shall re-implement it, and we
shall do it on CONFIG_SPARSEMEM_VMEMMAP, since we plan do make memory-hotplug
dependant on that, and drop support for CONFIG_SPARSEMEM &&
!CONFIG_SPARSEMEM_VMEMMAP environments.

I prepared two patches at [1] that drop the code and the CONFIG_MEMORY_HOTPLUG_foo
from the Kconfigs.

Let me know if you are fine with that and I shall send it.

Thanks

[1] https://github.com/leberus/linux/tree/deprecate-memhotplug-sh

-- 
Oscar Salvador
SUSE Labs