dt-bindings: atmel-sysreg: add microchip,sama7g5-shdwc

Add compatible for Microchip SAMA7G5's shutdown controller.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Documentation/devicetree/bindings/arm/atmel-sysregs.txt

@@ -91,7 +91,8 @@ SHDWC SAMA5D2-Compatible Shutdown Controller
 1) shdwc node
 
 required properties:
-- compatible: should be "atmel,sama5d2-shdwc" or "microchip,sam9x60-shdwc".
+- compatible: should be "atmel,sama5d2-shdwc", "microchip,sam9x60-shdwc" or
+  "microchip,sama7g5-shdwc"
 - reg: should contain registers location and length
 - clocks: phandle to input clock.
 - #address-cells: should be one. The cell is the wake-up input index.
@@ -103,7 +104,7 @@ optional properties:
   microseconds. It's usually a board-related property.
 - atmel,wakeup-rtc-timer: boolean to enable Real-Time Clock wake-up.
 
-optional microchip,sam9x60-shdwc properties:
+optional microchip,sam9x60-shdwc or microchip,sama7g5-shdwc properties:
 - atmel,wakeup-rtt-timer: boolean to enable Real-time Timer Wake-up.
 
 The node contains child nodes for each wake-up input that the platform uses.