powerpc/mm: fix memory hotplug BUG() on radix

[Michael Ellerman]

On Tue, 2017-01-03 at 20:39:51 UTC, Reza Arbab wrote:
> Memory hotplug is leading to hash page table calls, even on radix:
> 
> ...
> 	arch_add_memory
> 		create_section_mapping
> 			htab_bolt_mapping
> 				BUG_ON(!ppc_md.hpte_insert);
> 
> To fix, refactor {create,remove}_section_mapping() into hash__ and
> radix__ variants. Leave the radix versions stubbed for now.
> 
> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>
> Acked-by: Balbir Singh <bsingharora at gmail.com>
> Signed-off-by: Reza Arbab <arbab at linux.vnet.ibm.com>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/32b53c012e0bfe20b2745962a89db0

cheers