spi: sh-msiof: Add r8a774c0 support

Document RZ/G2E (R8A774C0) SoC bindings.
Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/spi/sh-msiof.txt

@@ -5,6 +5,7 @@ Required properties:
 			 "renesas,msiof-r8a7744" (RZ/G1N)
 			 "renesas,msiof-r8a7745" (RZ/G1E)
 			 "renesas,msiof-r8a774a1" (RZ/G2M)
+			 "renesas,msiof-r8a774c0" (RZ/G2E)
 			 "renesas,msiof-r8a7790" (R-Car H2)
 			 "renesas,msiof-r8a7791" (R-Car M2-W)
 			 "renesas,msiof-r8a7792" (R-Car V2H)