powerpc: Guard htab_dt_scan_hugepage_blocks appropriately

htab_dt_scan_hugepage_blocks is only used when CONFIG_HUGETLB_PAGE is
defined, so guard the declaration likewise.

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 14be408..7efcb9c 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -343,6 +343,7 @@
 	return 0;
 }
 
+#ifdef CONFIG_HUGETLB_PAGE
 /* Scan for 16G memory blocks that have been set aside for huge pages
  * and reserve those blocks for 16G huge pages.
  */
@@ -380,6 +381,7 @@
 	add_gpage(phys_addr, block_size, expected_pages);
 	return 0;
 }
+#endif /* CONFIG_HUGETLB_PAGE */
 
 static void __init htab_init_page_sizes(void)
 {