patch as-lock-macro-simplification

*** 1531,1546 ****
          }
  
          ASSERT(entities != NULL);
          /* process all segs in process's address space */
          as = p->p_as;
!         AS_LOCK_ENTER(as, &as->a_lock, RW_READER);
          for (seg = AS_SEGFIRST(as); seg != NULL;
              seg = AS_SEGNEXT(as, seg)) {
                  vmu_calculate_seg(entities, seg);
          }
!         AS_LOCK_EXIT(as, &as->a_lock);
  }
  
  /*
   * Free data created by previous call to vmu_calculate().
   */
--- 1531,1546 ----
          }
  
          ASSERT(entities != NULL);
          /* process all segs in process's address space */
          as = p->p_as;
!         AS_LOCK_ENTER(as, RW_READER);
          for (seg = AS_SEGFIRST(as); seg != NULL;
              seg = AS_SEGNEXT(as, seg)) {
                  vmu_calculate_seg(entities, seg);
          }
!         AS_LOCK_EXIT(as);
  }
  
  /*
   * Free data created by previous call to vmu_calculate().
   */