Fix calculation of dentry size

The PAD_TO function was incorrectly handling values that were already
aligned, which could lead to overruns of the dentry block.  Fix the
function, rename it to ALIGN, move it to ext4_utils.h, and use it
everywhere the dentry size is calculated.

Change-Id: Ie9778d2c6f72d3db9a3162e52882377a71b8420a
2 files changed