- Make use of pci_unmap_xxx storage optimization.
- In tg3_get_invariants, fix cacheline_sz_reg shifts.
  On 5703 chips, if latency timer is less than 64, set
  it to 64.
- In tg3_test_dma, only run the actual test on 5700/5701
  chips.  Aparently 5702/5703 revs have some problems.