mfd: hi655x-pmic: Fix missing return value check for devm_regmap_init_mmio_clk

Since devm_regmap_init_mmio_clk can fail, add return value checking.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Acked-by: NChen Feng <puck.chen@hisilicon.com>
Signed-off-by: NLee Jones <lee.jones@linaro.org>

drivers/mfd/hi655x-pmic.c

@@ -112,6 +112,8 @@ static int hi655x_pmic_probe(struct platform_device *pdev)
 
 	pmic->regmap = devm_regmap_init_mmio_clk(dev, NULL, base,
 						 &hi655x_regmap_config);
+	if (IS_ERR(pmic->regmap))
+		return PTR_ERR(pmic->regmap);
 
 	regmap_read(pmic->regmap, HI655X_BUS_ADDR(HI655X_VER_REG), &pmic->ver);
 	if ((pmic->ver < PMU_VER_START) || (pmic->ver > PMU_VER_END)) {