mfd: sec-core: Fix uninitialized 'regmap_rtc' on S2MPA01

Initialize the 'regmap_rtc' on S2MPA01 to some sane value. Sane at least
for S5M87X chipsets, not S2MPS/S2MPA but it won't be used because
rtc-s5m driver does not support S2MPA01.

This fixes following error:
drivers/mfd/sec-core.c:342:45: warning: ‘regmap_rtc’ may be used uninitialized in this function [-Wuninitialized]

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/sec-core.c

@@ -298,6 +298,13 @@ static int sec_pmic_probe(struct i2c_client *i2c,
 	switch (sec_pmic->device_type) {
 	case S2MPA01:
 		regmap = &s2mpa01_regmap_config;
+		/*
+		 * The rtc-s5m driver does not support S2MPA01 and there
+		 * is no mfd_cell for S2MPA01 RTC device.
+		 * However we must pass something to devm_regmap_init_i2c()
+		 * so use S5M-like regmap config even though it wouldn't work.
+		 */
+		regmap_rtc = &s5m_rtc_regmap_config;
 		break;
 	case S2MPS11X:
 		regmap = &s2mps11_regmap_config;