pinctrl: qcom-spmi-mpp: Fix input value report

Fix interpretation of the pmic_mpp_read() return code,
negative value means an error.
Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/qcom/pinctrl-spmi-mpp.c

@@ -577,11 +577,12 @@ static void pmic_mpp_config_dbg_show(struct pinctrl_dev *pctldev,
 
 		if (pad->input_enabled) {
 			ret = pmic_mpp_read(state, pad, PMIC_MPP_REG_RT_STS);
-			if (!ret) {
+			if (ret < 0)
+				return;
+
 			ret &= PMIC_MPP_REG_RT_STS_VAL_MASK;
 			pad->out_value = ret;
 		}
-		}
 
 		seq_printf(s, " %-4s", pad->output_enabled ? "out" : "in");
 		seq_printf(s, " %-4s", pad->analog_mode ? "ana" : "dig");