ASoC: Refactor WM8958 DSP to support additional algorithms

In preparation for the addition of additional WM8958 algorithms
reorganise the code to make it easier to add such support later.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>
diff --git a/sound/soc/codecs/wm8994.h b/sound/soc/codecs/wm8994.h
index 1aa365b..a4bfde8 100644
--- a/sound/soc/codecs/wm8994.h
+++ b/sound/soc/codecs/wm8994.h
@@ -116,6 +116,7 @@
 	unsigned int aif1clk_disable:1;
 	unsigned int aif2clk_disable:1;
 
+	int dsp_active;
 	const struct firmware *cur_fw;
 	const struct firmware *mbc;
 };