945fa6c58f
interrupt map, interrupt handler and dma maps. Also prevent call to bus_dmamap_destroy() when bus_dmamap_create() failed. The nfe_free_* routines assume, the map pointers are NULL but they are actually undefined. Make the assumption true by making them NULL in the error path of bus_dmamap_create(). All together, this fixes crashes when nfe_attach() fails. ok martin@