f2fs: fix to do sanity check for sb/cp fields correctly

f2fs: fix to do sanity check for sb/cp fields correctly

commit 65ddf6564843890a58ee3b18bb46ce67d96333fb upstream.

This patch fixes below problems of sb/cp sanity check:
- in sanity_check_raw_superi(), it missed to consider log header
blocks while cp_payload check.
- in f2fs_sanity_check_ckpt(), it missed to check nat_bits_blocks.

Cc: <stable@kernel.org>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>