ASoC: samsung: i2s: Remove redundant null check before clk_disable_unprepare

Because clk_disable_unprepare() already checked NULL clock parameter,
so the additional check is unnecessary, just remove it.
Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Link: https://lore.kernel.org/r/20201029084137.28771-1-vulab@iscas.ac.cnSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/samsung/i2s.c

@@ -1212,8 +1212,7 @@ static int i2s_runtime_suspend(struct device *dev)
 	priv->suspend_i2scon = readl(priv->addr + I2SCON);
 	priv->suspend_i2spsr = readl(priv->addr + I2SPSR);
 
-	if (priv->op_clk)
-		clk_disable_unprepare(priv->op_clk);
+	clk_disable_unprepare(priv->op_clk);
 	clk_disable_unprepare(priv->clk);
 
 	return 0;