ALSA: oxfw: Move to its own directory

Followed commits add much codes. To make the work easy, this commit creates
own directory and move current file to it.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/firewire/Makefile b/sound/firewire/Makefile
index 5ed6fb7..8b37f08 100644
--- a/sound/firewire/Makefile
+++ b/sound/firewire/Makefile
@@ -6,7 +6,7 @@
 
 obj-$(CONFIG_SND_FIREWIRE_LIB) += snd-firewire-lib.o
 obj-$(CONFIG_SND_DICE) += dice/
-obj-$(CONFIG_SND_OXFW) += snd-oxfw.o
+obj-$(CONFIG_SND_OXFW) += oxfw/
 obj-$(CONFIG_SND_ISIGHT) += snd-isight.o
 obj-$(CONFIG_SND_SCS1X) += snd-scs1x.o
 obj-$(CONFIG_SND_FIREWORKS) += fireworks/