e2fsck: fix j_maxlen if the file system is exactly 1 << 32 blocks

If the external journal device has exactly 1 << 32 blocks,
journal->j_maxlen would get set to zero, which would cause e2fsck to
declare the journal to be invalid.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
1 file changed