ALSA: bebob: add Digidesign Mbox 2 Pro support

This device is based on DM1000E, and BeBoB version 1 firmware is
installed.

$ cat /proc/asound/cards
 0 [Pro            ]: BeBoB - Mbox 2 Pro
                      DIGIDESIGN Mbox 2 Pro (id:1, rev:1),
		      GUID 00a07e0100a90000 at fw1.0, S400

$ cat /proc/asound/Pro/firewire/firmware
Manufacturer:	bridgeCo
Protocol Ver:	1
Build Ver:		0
GUID:		0x00A07E0100A90000
Model ID:		0x01
Model Rev:		1
Firmware Date:	20071031
Firmware Time:	034402
Firmware ID:	0xA9
Firmware Ver:	16777215
Base Addr:		0x20080000
Max Size:		1572864
Loader Date:	20051207
Loader Time:	205554

With this patch, ALSA BeBoB driver can start packet streaming to/from
this model, while as a default, internal multiplexer of this model is
not initialized and generates no sound even if the driver transfers
any packets with PCM samples. To hear any sounds from this model,
userspace applications should be developed to set parameters to the
internal multiplexer. You can see raw information in FFADO website:
http://subversion.ffado.org/wiki/AvcModels/DigiDesignMboxPro2



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