10139 smatch fixes for usr/src/cmd/stat

*** 456,466 ****
                  pos = iodevs;
                  while (pos && nr_iodevs) {
                          tmp = pos;
                          pos = pos->is_next;
  
!                         if (df && df->if_skip_floppy &&
                              strncmp(tmp->is_name, "fd", 2) == 0)
                                  continue;
  
                          list_del(&iodevs, tmp);
                          insert_iodev(ss, tmp);
--- 456,466 ----
                  pos = iodevs;
                  while (pos && nr_iodevs) {
                          tmp = pos;
                          pos = pos->is_next;
  
!                         if (df->if_skip_floppy &&
                              strncmp(tmp->is_name, "fd", 2) == 0)
                                  continue;
  
                          list_del(&iodevs, tmp);
                          insert_iodev(ss, tmp);