power: pmic: tps65218: Add DCDC3 configuration

Some boards like am437x-gp-evm require dcdc3 also to be configured
as it feeds on to ddr. Hence add the capability as well.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>

drivers/power/pmic/pmic_tps65218.c

@@ -96,7 +96,8 @@ int tps65218_reg_write(uchar prot_level, uchar dest_reg, uchar dest_val,
 int tps65218_voltage_update(uchar dc_cntrl_reg, uchar volt_sel)
 {
 	if ((dc_cntrl_reg != TPS65218_DCDC1) &&
-	    (dc_cntrl_reg != TPS65218_DCDC2))
+	    (dc_cntrl_reg != TPS65218_DCDC2) &&
+	    (dc_cntrl_reg != TPS65218_DCDC3))
 		return 1;
 
 	/* set voltage level */