f2fs: use inner macro GFP_F2FS_ZERO for simplification

Use inner macro GFP_F2FS_ZERO to instead of GFP_NOFS | __GFP_ZERO for
simplification of code.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

fs/f2fs/node.c

@@ -1577,7 +1577,7 @@ static int ra_sum_pages(struct f2fs_sb_info *sbi, struct list_head *pages,
 
 	for (; page_idx < start + nrpages; page_idx++) {
 		/* alloc temporal page for read node summary info*/
-		page = alloc_page(GFP_NOFS | __GFP_ZERO);
+		page = alloc_page(GFP_F2FS_ZERO);
 		if (!page) {
 			struct page *tmp;
 			list_for_each_entry_safe(page, tmp, pages, lru) {

fs/f2fs/recovery.c

@@ -377,7 +377,7 @@ static int recover_data(struct f2fs_sb_info *sbi,
 	blkaddr = NEXT_FREE_BLKADDR(sbi, curseg);
 
 	/* read node page */
-	page = alloc_page(GFP_NOFS | __GFP_ZERO);
+	page = alloc_page(GFP_F2FS_ZERO);
 	if (!page)
 		return -ENOMEM;
 

fs/f2fs/super.c

@@ -332,7 +332,7 @@ static struct inode *f2fs_alloc_inode(struct super_block *sb)
 {
 	struct f2fs_inode_info *fi;
 
-	fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_NOFS | __GFP_ZERO);
+	fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_F2FS_ZERO);
 	if (!fi)
 		return NULL;