dt-bindings: thermal: rcar-thermal: document R8A77970 bindings

Document  the R-Car V3M (R8A77970) SoC in the Renesas R-Car gen2 thermal
bindings. The hardware is the same as  in the R-Car D3 (R8A77995) plus an
extra status register.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: NSimon Horman <horms+renesas@verge.net.au>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>

Documentation/devicetree/bindings/thermal/rcar-thermal.txt

@@ -4,7 +4,7 @@ Required properties:
 - compatible		: "renesas,thermal-<soctype>",
 			   "renesas,rcar-gen2-thermal" (with thermal-zone) or
 			   "renesas,rcar-thermal" (without thermal-zone) as
-                           fallback except R-Car D3.
+                           fallback except R-Car V3M/D3.
 			  Examples with soctypes are:
 			    - "renesas,thermal-r8a73a4" (R-Mobile APE6)
 			    - "renesas,thermal-r8a7743" (RZ/G1M)
@@ -14,6 +14,7 @@ Required properties:
 			    - "renesas,thermal-r8a7791" (R-Car M2-W)
 			    - "renesas,thermal-r8a7792" (R-Car V2H)
 			    - "renesas,thermal-r8a7793" (R-Car M2-N)
+			    - "renesas,thermal-r8a77970" (R-Car V3M)
 			    - "renesas,thermal-r8a77995" (R-Car D3)
 - reg			: Address range of the thermal registers.
 			  The 1st reg will be recognized as common register
@@ -22,7 +23,7 @@ Required properties:
 Option properties:
 
 - interrupts		: If present should contain 3 interrupts for
-                          R-Car D3 or 1 interrupt otherwise.
+                          R-Car V3M/D3 or 1 interrupt otherwise.
 
 Example (non interrupt support):