ASoC: rt5682: remove unwanted btn_type assignment

The following dev_err() is intended to print unexpected btn_type.
Removes the unwanted btn_type assignment.
Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Link: https://lore.kernel.org/r/20200430082231.151127-7-tzungbi@google.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/rt5682.c

@@ -1134,7 +1134,6 @@ static void rt5682_jack_detect_handler(struct work_struct *work)
 			case 0x0000: /* unpressed */
 				break;
 			default:
-				btn_type = 0;
 				dev_err(rt5682->component->dev,
 					"Unexpected button code 0x%04x\n",
 					btn_type);