ALSA: bebob: Add hwdep interface

This interface is designed for mixer/control application. By using hwdep
interface, the application can get information about firewire node, can
lock/unlock kernel streaming and can get notification at starting/stopping
kernel streaming.

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

sound/firewire/Kconfig

@@ -84,6 +84,7 @@ config SND_BEBOB
 	select SND_FIREWIRE_LIB
 	select SND_RAWMIDI
 	select SND_PCM
+	select SND_HWDEP
         help
 	 Say Y here to include support for FireWire devices based
 	 on BridgeCo DM1000/DM1100/DM1500 with BeBoB firmware: