support for Tekram DC395U2W cards.
Add a fix submitted by joerg@ to correctly report some errors to CAM.
Use bus_dma instead of the remaining vtophys().
prototype for trm_detach and freeing all resources.
While I'm there, handle better errors in trm_attach and remove the
PCI_BASE_ADDR0 definition, since it's what PCIR_MAPS is used for.
MFC after: 3 days
