ASoC: Add missing break in WM8994 probe

This error would have no effect on current silicon revisions, the fall
through case has the same behaviour.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>
diff --git a/sound/soc/codecs/wm8994.c b/sound/soc/codecs/wm8994.c
index 09e680a..b393f9f 100644
--- a/sound/soc/codecs/wm8994.c
+++ b/sound/soc/codecs/wm8994.c
@@ -2981,6 +2981,7 @@
 			wm8994->hubs.dcs_readback_mode = 1;
 			break;
 		}
+		break;
 
 	case WM8958:
 		wm8994->hubs.dcs_readback_mode = 1;