883428f9df
total of 6 interrupt resources for scc(4) on macio(4). This is 3 per channel, of which the 1st of each channel is the interrupt associated with the SCC. The other 2 are for DMA operation. Change scc_bfe_attach() to accept an argument that's the number of interrupts per channel (ipc) and change each bus front-end (bfe) to pass that argument through a wrapper for the device_attach method. For now, we only allocate the 1st interrupt of each channel to perserve behaviour.