regulator: axp20x: Simplify axp20x_is_polyphase_slave implementation

The code to handle AXP803_ID and AXP813_ID cases are exactly the same.
Make the switch-case fall through to avoid duplicate code.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/regulator/axp20x-regulator.c

@@ -657,6 +657,7 @@ static bool axp20x_is_polyphase_slave(struct axp20x_dev *axp20x, int id)
 	 */
 	switch (axp20x->variant) {
 	case AXP803_ID:
+	case AXP813_ID:
 		regmap_read(axp20x->regmap, AXP803_POLYPHASE_CTRL, &reg);
 
 		switch (id) {
@@ -681,17 +682,6 @@ static bool axp20x_is_polyphase_slave(struct axp20x_dev *axp20x, int id)
 		}
 		break;
 
-	case AXP813_ID:
-		regmap_read(axp20x->regmap, AXP803_POLYPHASE_CTRL, &reg);
-
-		switch (id) {
-		case AXP803_DCDC3:
-			return !!(reg & BIT(6));
-		case AXP803_DCDC6:
-			return !!(reg & BIT(5));
-		}
-		break;
-
 	default:
 		return false;
 	}