powerpc/cell: Drop support for 64K local store on 4K kernels

Back in the olden days we added support for using 64K pages to map the
SPU (Synergistic Processing Unit) local store on Cell, when the main
kernel was using 4K pages.

This was useful at the time because distros were using 4K pages, but
using 64K pages on the SPUs could reduce TLB pressure there.

However these days the number of Cell users is approaching zero, and
supporting this option adds unpleasant complexity to the memory
management code.

So drop the option, CONFIG_SPU_FS_64K_LS, and all related code.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Jeremy Kerr <jk@ozlabs.org>

arch/powerpc/mm/hugetlbpage.c

@@ -808,14 +808,6 @@ static int __init add_huge_page_size(unsigned long long size)
 	if ((mmu_psize = shift_to_mmu_psize(shift)) < 0)
 		return -EINVAL;
 
-#ifdef CONFIG_SPU_FS_64K_LS
-	/* Disable support for 64K huge pages when 64K SPU local store
-	 * support is enabled as the current implementation conflicts.
-	 */
-	if (shift == PAGE_SHIFT_64K)
-		return -EINVAL;
-#endif /* CONFIG_SPU_FS_64K_LS */
-
 	BUG_ON(mmu_psize_defs[mmu_psize].shift != shift);
 
 	/* Return if huge page size has already been setup */