f2fs: clean up w/ fscrypt_is_bounce_page()

Just cleanup, no logic changes.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Author: chaseyu

fs/f2fs/data.c

@@ -53,7 +53,7 @@ bool f2fs_is_cp_guaranteed(struct page *page)
 	struct inode *inode;
 	struct f2fs_sb_info *sbi;
 
-	if (!mapping)
+	if (fscrypt_is_bounce_page(page))
 		return false;
 
 	inode = mapping->host;