dt-bindings: i2c: rcar: Add r8a774b1 support

Document RZ/G2N (R8A774B1) I2C compatibility with the relevant driver
dt-bindings.
Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Documentation/devicetree/bindings/i2c/renesas,i2c.txt

@@ -7,6 +7,7 @@ Required properties:
 	"renesas,i2c-r8a7745" if the device is a part of a R8A7745 SoC.
 	"renesas,i2c-r8a77470" if the device is a part of a R8A77470 SoC.
 	"renesas,i2c-r8a774a1" if the device is a part of a R8A774A1 SoC.
+	"renesas,i2c-r8a774b1" if the device is a part of a R8A774B1 SoC.
 	"renesas,i2c-r8a774c0" if the device is a part of a R8A774C0 SoC.
 	"renesas,i2c-r8a7778" if the device is a part of a R8A7778 SoC.
 	"renesas,i2c-r8a7779" if the device is a part of a R8A7779 SoC.