ALSA: oxfw: add support for APOGEE duet FireWire

This commit adds support for APOGEE duet FireWire, launched 2007, already
discontinued. This model uses Oxford Semiconductor FW971 as its
communication engine. Below is information on Configuration ROM of this
unit. The unit supports some AV/C commands defined by Audio subunit
specification and vendor dependent commands.

$ ./hinawa-config-rom-printer /dev/fw1
{ 'bus-info': { 'adj': False,
                'bmc': False,
                'chip_ID': 42949742248,
                'cmc': False,
                'cyc_clk_acc': 255,
                'generation': 0,
                'imc': False,
                'isc': True,
                'link_spd': 3,
                'max_ROM': 0,
                'max_rec': 64,
                'name': '1394',
                'node_vendor_ID': 987,
                'pmc': False},
  'root-directory': [ ['VENDOR', 987],
                      ['DESCRIPTOR', 'Apogee Electronics'],
                      ['MODEL', 122333],
                      ['DESCRIPTOR', 'Duet'],
                      [ 'NODE_CAPABILITIES',
                        { 'addressing': {'64': True, 'fix': True, 'prv': False},
                          'misc': {'int': False, 'ms': False, 'spt': True},
                          'state': { 'atn': False,
                                     'ded': False,
                                     'drq': True,
                                     'elo': False,
                                     'init': False,
                                     'lst': True,
                                     'off': False},
                          'testing': {'bas': False, 'ext': False}}],
                      [ 'UNIT',
                        [ ['SPECIFIER_ID', 41005],
                          ['VERSION', 65537],
                          ['MODEL', 122333],
                          ['DESCRIPTOR', 'Duet']]]]}

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>