net: macb: Add sam9x60-macb compatibility string

Add this new compatibility string for matching sam9x60 product
macb.

Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
diff --git a/drivers/net/macb.c b/drivers/net/macb.c
index 377188e..1a532b0 100644
--- a/drivers/net/macb.c
+++ b/drivers/net/macb.c
@@ -1321,6 +1321,7 @@
 static const struct udevice_id macb_eth_ids[] = {
 	{ .compatible = "cdns,macb" },
 	{ .compatible = "cdns,at91sam9260-macb" },
+	{ .compatible = "cdns,sam9x60-macb" },
 	{ .compatible = "atmel,sama5d2-gem" },
 	{ .compatible = "atmel,sama5d3-gem" },
 	{ .compatible = "atmel,sama5d4-gem", .data = (ulong)&sama5d4_config },