Revert to a proper state when gelic_card_kick_txdma() fails:
- Don't trigger BUG_ON when releasing the unsent tx descriptor
- Reset the tx chain head since the tail was not modified and
  hence not in sync
- Unlink the released descriptor bus address from its predecessor
Signed-off-by: Andre Heider <a.heider@gmail.com>
Acked-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>