ext4/027: Correct the right code of block and inode bitmap

ext4/027: Correct the right code of block and inode bitmap

Observed occasional failure of this test sometimes say with 64k config
and small device size. Reason is we were grepping for wrong values for
inode and block bitmap.

Correct those values according to [1] to fix this test.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/fs/ext4/fsmap.h#n53

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>