hbitmap: add 'pos < size' asserts

For now, fail in hbitmap_set on start + count > size will come from
hbitmap_set
  hb_count_between
    hbitmap_iter_init
      assert(pos < hb->size)

This patch adds such checks to set/get/reset functions of hbitmap.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 1465924093-76875-2-git-send-email-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
