message: Improve Match Part Constraints logic
  We do not need to call FSubsetPartCnstr() twice to check for equality.
  Two part constraints can are equal if their lengths match and
  one is subset of the other.
diff: @@ -178,7 +178,7 @@ CPhysicalPartitionSelector::FMatchPartCnstr
  return NULL == m_ppartcnstrmap && NULL == ppartcnstrmap;
  }
  - return FSubsetPartCnstr(m_ppartcnstrmap, ppartcnstrmap) &&
  + return m_ppartcnstrmap->UlEntries() == ppartcnstrmap->UlEntries() &&
  FSubsetPartCnstr(ppartcnstrmap, m_ppartcnstrmap);
  }
  