regulator/lp3971: vol_map out of bounds in lp3971_{ldo,dcdc}_set_voltage()

After `for (val = LDO_VOL_MIN_IDX; val <= LDO_VOL_MAX_IDX; val++)', if no break
occurs, val reaches LDO_VOL_MIN_IDX + 1, which is out of bounds for
ldo45_voltage_map[] and ldo123_voltage_map[].

Similarly BUCK_TARGET_VOL_MAX_IDX + 1 is out of bounds for buck_voltage_map[].

Signed-off-by: Roel Kluin <[e-mail]>
Acked-by: Mark Brown <[e-mail]>
Signed-off-by: Liam Girdwood <[e-mail]>

drivers/regulator/lp3971.c

···
 		if (vol_map[val] >= min_vol)
 			break;
 
-	if (vol_map[val] > max_vol)
+	if (val > LDO_VOL_MAX_IDX || vol_map[val] > max_vol)
 		return -EINVAL;
 
 	return lp3971_set_bits(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo),
···
 		if (vol_map[val] >= min_vol)
 			break;
 
-	if (vol_map[val] > max_vol)
+	if (val > BUCK_TARGET_VOL_MAX_IDX || vol_map[val] > max_vol)
 		return -EINVAL;
 
 	ret = lp3971_set_bits(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck),