M68k IDE:
  - Update for new-style low-level IDE operations. Since so far no single
    m68k platform uses ISA/PCI I/O space for IDE, we always use the `raw' MMIO
    versions.
  - ATA_ARCH_LOCK was renamed to IDE_ARCH_LOCK
  - Define ide_ack_intr() and set IDE_ARCH_ACK_INTR