powerpc/mm: Define MAX_PHYSMEM_BITS for all 64-bit configs

[Michael Ellerman]

On Tue, 2019-04-09 at 06:03:24 UTC, Michael Ellerman wrote:
> The recent commit 8bc086899816 ("powerpc/mm: Only define
> MAX_PHYSMEM_BITS in SPARSEMEM configurations") removed our definition
> of MAX_PHYSMEM_BITS when SPARSEMEM is disabled.
> 
> This inadvertently broke some 64-bit FLATMEM using configs with eg:
> 
>   arch/powerpc/include/asm/book3s/64/mmu-hash.h:584:6: error: "MAX_PHYSMEM_BITS" is not defined, evaluates to 0
>    #if (MAX_PHYSMEM_BITS > MAX_EA_BITS_PER_CONTEXT)
>         ^~~~~~~~~~~~~~~~
> 
> Fix it by making sure we define MAX_PHYSMEM_BITS for all 64-bit
> configs regardless of SPARSEMEM.
> 
> Fixes: 8bc086899816 ("powerpc/mm: Only define MAX_PHYSMEM_BITS in SPARSEMEM configurations")
> Reported-by: Andreas Schwab <schwab at linux-m68k.org>
> Reported-by: Hugh Dickins <hughd at google.com>
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar at linux.ibm.com>

Applied to powerpc fixes.

https://git.kernel.org/powerpc/c/cf7cf6977f531acd5dfe55250d0ee8cb

cheers