cpuusagetop.c: Missing break in switch errors spotted by Coverity

Original author: rlong

CID 1399726: Missing break in switch in task_usage(). CID 1399728: Missing break in switch in task_usage(). CID 1399742: Missing break in switch in task_usage().

CID 1399726

233            continue;
   CID 1399726 (#1 of 1): Missing break in switch (MISSING_BREAK)unterminated_case: The case for value 2U is not terminated by a break statement.
234        case RTEMS_TOP_SORT_CURRENT_PRI:
235          if (
236            _Thread_Get_priority( thread )
237              > _Thread_Get_priority( data->tasks[j] )
238          ) {
239            continue;
240          }
   fallthrough: The above case falls through to this one.

CID 1399728

230            continue;
   CID 1399728 (#1 of 1): Missing break in switch (MISSING_BREAK)unterminated_case: The case for value 1U is not terminated by a break statement.
231        case RTEMS_TOP_SORT_REAL_PRI:
232          if (thread->Real_priority.priority > data->tasks[j]->Real_priority.priority)
233            continue;
   fallthrough: The above case falls through to this one.
234        case RTEMS_TOP_SORT_CURRENT_PRI:

CID 1399742

226            continue;
   CID 1399742 (#1 of 1): Missing break in switch (MISSING_BREAK)unterminated_case: The case for value 3U is not terminated by a break statement.
227        case RTEMS_TOP_SORT_TOTAL:
228          if (CPU_usage_Equal_to(&usage, &data->zero) ||
229              CPU_usage_Less_than(&usage, &data->usage[j]))
230            continue;
   fallthrough: The above case falls through to this one.
231        case RTEMS_TOP_SORT_REAL_PRI: