ALSA: AACI: make fifo variables more explanitory

Improve commenting and change fifo variable names to reflect their
meanings.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/sound/arm/aaci.h b/sound/arm/aaci.h
index 198750d..5791bd5 100644
--- a/sound/arm/aaci.h
+++ b/sound/arm/aaci.h
@@ -219,14 +219,14 @@
 	void			*end;
 	void			*ptr;
 	int			bytes;
-	unsigned int		fifosz;
+	unsigned int		fifo_bytes;
 };
 
 struct aaci {
 	struct amba_device	*dev;
 	struct snd_card		*card;
 	void			__iomem *base;
-	unsigned int		fifosize;
+	unsigned int		fifo_depth;
 	unsigned int		users;
 	struct mutex		irq_lock;