dt-bindings: i2c: sh_mobile: Add r8a774a1 support

Document RZ/G2M (R8A774A1) SoC bindings.
Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt

@@ -6,6 +6,7 @@ Required properties:
 			- "renesas,iic-r8a7740" (R-Mobile A1)
 			- "renesas,iic-r8a7743" (RZ/G1M)
 			- "renesas,iic-r8a7745" (RZ/G1E)
+			- "renesas,iic-r8a774a1" (RZ/G2M)
 			- "renesas,iic-r8a7790" (R-Car H2)
 			- "renesas,iic-r8a7791" (R-Car M2-W)
 			- "renesas,iic-r8a7792" (R-Car V2H)
@@ -17,7 +18,8 @@ Required properties:
 			- "renesas,iic-sh73a0" (SH-Mobile AG5)
 			- "renesas,rcar-gen2-iic" (generic R-Car Gen2 or RZ/G1
 							compatible device)
-			- "renesas,rcar-gen3-iic" (generic R-Car Gen3 compatible device)
+			- "renesas,rcar-gen3-iic" (generic R-Car Gen3 or RZ/G2
+							compatible device)
 			- "renesas,rmobile-iic" (generic device)
 
 			When compatible with a generic R-Car version, nodes