5179 remove unused ZFS ARC functions

*** 1308,1334 ****
          ARCSTAT_INCR(arcstat_meta_used, -space);
          ASSERT(arc_size >= space);
          atomic_add_64(&arc_size, -space);
  }
  
- void *
- arc_data_buf_alloc(uint64_t size)
- {
-         if (arc_evict_needed(ARC_BUFC_DATA))
-                 cv_signal(&arc_reclaim_thr_cv);
-         atomic_add_64(&arc_size, size);
-         return (zio_data_buf_alloc(size));
- }
- 
- void
- arc_data_buf_free(void *buf, uint64_t size)
- {
-         zio_data_buf_free(buf, size);
-         ASSERT(arc_size >= size);
-         atomic_add_64(&arc_size, -size);
- }
- 
  arc_buf_t *
  arc_buf_alloc(spa_t *spa, int size, void *tag, arc_buf_contents_t type)
  {
          arc_buf_hdr_t *hdr;
          arc_buf_t *buf;
--- 1308,1317 ----