arm64: dts: exynos: enable PMIC wakeup from suspend on TM2

The RTC on S2MPS13 PMIC can wakeup the system from suspend to RAM.
Add a generic property for this.

Link: https://lore.kernel.org/r/20210614193309.20248-2-krzysztof.kozlowski@canonical.comSigned-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20210420164943.11152-11-krzysztof.kozlowski@canonical.comSigned-off-by: Olof Johansson <olof@lixom.net>

arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi

@@ -391,6 +391,7 @@ pmic@66 {
 		interrupts = <7 IRQ_TYPE_LEVEL_LOW>;
 		reg = <0x66>;
 		samsung,s2mps11-wrstbi-ground;
+		wakeup-source;
 
 		s2mps13_osc: clocks {
 			compatible = "samsung,s2mps13-clk";