MFC r222279:

MFC r222279:
  Do not truncate available disk space to the closest track boundary.

MFC r222341:
  Some partitioning tools may have a different opinion about disk
  geometry and partitions may start from withing the first track.
  If we found such partitions, then do not reserve space of the
  first track, only first sector.

git-svn-id: svn://svn.freebsd.org/base/stable/8@230570 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f