net: sh_eth: Add remaining Gen2 DT compatible

Add compatible strings for R8A7790, R8A7793 and R8A7794, since the
contemporary DTs use those don't have a generic match value.
Signed-off-by: NMarek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Cc: Joe Hershberger <joe.hershberger@ni.com>

drivers/net/sh_eth.c

@@ -906,7 +906,10 @@ int sh_ether_ofdata_to_platdata(struct udevice *dev)
 }
 
 static const struct udevice_id sh_ether_ids[] = {
+	{ .compatible = "renesas,ether-r8a7790" },
 	{ .compatible = "renesas,ether-r8a7791" },
+	{ .compatible = "renesas,ether-r8a7793" },
+	{ .compatible = "renesas,ether-r8a7794" },
 	{ }
 };