ASoC: Initial WM8904 CODEC driver

The WM8904 is a high performance ultra-low power stereo CODEC
optimised for portable audio applications, with features including
a class W amplifier, FLL with free running mode, Mobile ReTune and
ground referenced headphone and line outputs.

Support for some features, most particularly the digital microphone
interface, is not yet present.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile
index dbaecb1..0471d90 100644
--- a/sound/soc/codecs/Makefile
+++ b/sound/soc/codecs/Makefile
@@ -36,6 +36,7 @@
 snd-soc-wm8776-objs := wm8776.o
 snd-soc-wm8900-objs := wm8900.o
 snd-soc-wm8903-objs := wm8903.o
+snd-soc-wm8904-objs := wm8904.o
 snd-soc-wm8940-objs := wm8940.o
 snd-soc-wm8960-objs := wm8960.o
 snd-soc-wm8961-objs := wm8961.o
@@ -92,6 +93,7 @@
 obj-$(CONFIG_SND_SOC_WM8776)	+= snd-soc-wm8776.o
 obj-$(CONFIG_SND_SOC_WM8900)	+= snd-soc-wm8900.o
 obj-$(CONFIG_SND_SOC_WM8903)	+= snd-soc-wm8903.o
+obj-$(CONFIG_SND_SOC_WM8904)	+= snd-soc-wm8904.o
 obj-$(CONFIG_SND_SOC_WM8971)	+= snd-soc-wm8971.o
 obj-$(CONFIG_SND_SOC_WM8974)	+= snd-soc-wm8974.o
 obj-$(CONFIG_SND_SOC_WM8940)	+= snd-soc-wm8940.o