mm/PPC: use free_highmem_page() to free highmem pages into buddy system

Use helper function free_highmem_page() to free highmem pages into
the buddy system.
Signed-off-by: NJiang Liu <jiang.liu@huawei.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: "Suzuki K. Poulose" <suzuki@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/powerpc/mm/mem.c

@@ -352,13 +352,9 @@ void __init mem_init(void)
 			struct page *page = pfn_to_page(pfn);
 			if (memblock_is_reserved(paddr))
 				continue;
-			ClearPageReserved(page);
-			init_page_count(page);
-			__free_page(page);
-			totalhigh_pages++;
+			free_highmem_page(page);
 			reservedpages--;
 		}
-		totalram_pages += totalhigh_pages;
 		printk(KERN_DEBUG "High memory: %luk\n",
 		       totalhigh_pages << (PAGE_SHIFT-10));
 	}