[FIX] Normalize loops outside the SCoP during schedule generation

  We build the schedule based on a traversal of the region and accumulate
  information for each loop in it. The total schedule is associated with the
  loop surrounding the SCoP, though it can happen that there are blocks in the
  SCoP which are part of loops that are only partially in the SCoP. Instead of
  associating information with them (they are not part of the SCoP and
  consequently are not modeled) we have to associate the schedule information
  with the surrounding loop if any.

  This fixes bug 25240.

llvm-svn: 250668