ASoC: rt5645: Remove return value in jack detect work

"ASoC: rt5645: Check if codec is initialized in workqueue handler"
adds a check if codec is NULL in rt5645_irq_detection, which
returns an int. However, "ASoC: rt5645: Remove irq_jack_detection
function" removes that function, and moves the code in
jack_detect_work, which returns void.

Remove the return value to fix compilation warning.
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/rt5645.c

@@ -2928,7 +2928,7 @@ static void rt5645_jack_detect_work(struct work_struct *work)
 	int val, btn_type, gpio_state = 0, report = 0;
 
 	if (!rt5645->codec)
-		return -EINVAL;
+		return;
 
 	switch (rt5645->pdata.jd_mode) {
 	case 0: /* Not using rt5645 JD */