ext4: protect journal inode's blocks using block_validity

ext4: protect journal inode's blocks using block_validity

[ Upstream commit 345c0dbf3a30872d9b204db96b5857cd00808cae ]

Add the blocks which belong to the journal inode to block_validity's
system zone so attempts to deallocate or overwrite the journal due a
corrupted file system where the journal blocks are also claimed by
another inode.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202879
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>