f2fs: support superblock checksum

Now we support crc32 checksum for superblock.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Junling Zheng <zhengjunling@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 9166585..10770fd8 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -150,6 +150,7 @@
 #define F2FS_FEATURE_INODE_CRTIME	0x0100
 #define F2FS_FEATURE_LOST_FOUND		0x0200
 #define F2FS_FEATURE_VERITY		0x0400	/* reserved */
+#define F2FS_FEATURE_SB_CHKSUM		0x0800
 
 #define F2FS_HAS_FEATURE(sb, mask)					\
 	((F2FS_SB(sb)->raw_super->feature & cpu_to_le32(mask)) != 0)
@@ -3460,6 +3461,7 @@
 F2FS_FEATURE_FUNCS(quota_ino, QUOTA_INO);
 F2FS_FEATURE_FUNCS(inode_crtime, INODE_CRTIME);
 F2FS_FEATURE_FUNCS(lost_found, LOST_FOUND);
+F2FS_FEATURE_FUNCS(sb_chksum, SB_CHKSUM);
 
 #ifdef CONFIG_BLK_DEV_ZONED
 static inline int get_blkz_type(struct f2fs_sb_info *sbi,