6583 remove whole-process swapping

*** 1213,1224 ****
          nrp->req = req;
          nrp->cr = cr;
          nrp->ro = ro;
          nrp->thread = curthread;
  
-         ASSERT(curthread->t_schedflag & TS_DONT_SWAP);
- 
          /*
           * Look to see if there is already a cluster started
           * for this file.
           */
          mutex_enter(&rfs_async_write_lock);
--- 1213,1222 ----