ASoC: wm8994: Report any low impedance accessory as a headphone

Report any accessory with a low impedance as a headphone, previously
anything other than a short or microphone would not be reported at all.
The most likely reason is a microphone with incorrect polarity.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/codecs/wm8994.c b/sound/soc/codecs/wm8994.c
index b047bfa..11ca19b 100644
--- a/sound/soc/codecs/wm8994.c
+++ b/sound/soc/codecs/wm8994.c
@@ -3089,7 +3089,7 @@
 	}
 
 
-	if (wm8994->mic_detecting && status & 0x4) {
+	if (wm8994->mic_detecting && status & 0xfc) {
 		dev_dbg(codec->dev, "Detected headphone\n");
 		wm8994->mic_detecting = false;