powerpc/mm: remove a couple of #ifdef CONFIG_PPC_64K_PAGES in mm/slice.c

This patch replaces a couple of #ifdef CONFIG_PPC_64K_PAGES
by IS_ENABLED(CONFIG_PPC_64K_PAGES) to improve code maintainability.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/mm/slice.c

@@ -606,14 +606,13 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
 	newaddr = slice_find_area(mm, len, &potential_mask,
 				  psize, topdown, high_limit);
 
-#ifdef CONFIG_PPC_64K_PAGES
-	if (newaddr == -ENOMEM && psize == MMU_PAGE_64K) {
+	if (IS_ENABLED(CONFIG_PPC_64K_PAGES) && newaddr == -ENOMEM &&
+	    psize == MMU_PAGE_64K) {
 		/* retry the search with 4k-page slices included */
 		slice_or_mask(&potential_mask, &potential_mask, compat_maskp);
 		newaddr = slice_find_area(mm, len, &potential_mask,
 					  psize, topdown, high_limit);
 	}
-#endif
 
 	if (newaddr == -ENOMEM)
 		return -ENOMEM;
@@ -784,9 +783,9 @@ int slice_is_hugepage_only_range(struct mm_struct *mm, unsigned long addr,
 	VM_BUG_ON(radix_enabled());
 
 	maskp = slice_mask_for_size(&mm->context, psize);
-#ifdef CONFIG_PPC_64K_PAGES
+
 	/* We need to account for 4k slices too */
-	if (psize == MMU_PAGE_64K) {
+	if (IS_ENABLED(CONFIG_PPC_64K_PAGES) && psize == MMU_PAGE_64K) {
 		const struct slice_mask *compat_maskp;
 		struct slice_mask available;
 
@@ -794,7 +793,6 @@ int slice_is_hugepage_only_range(struct mm_struct *mm, unsigned long addr,
 		slice_or_mask(&available, maskp, compat_maskp);
 		return !slice_check_range_fits(mm, &available, addr, len);
 	}
-#endif
 
 	return !slice_check_range_fits(mm, maskp, addr, len);
 }