net: dsa: bcm_sf2: Update compatible string for 7278B0

Update the compatible string and Device Tree binding document for
7278B0.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/brcm,bcm7445-switch-v4.0.txt

@@ -2,7 +2,10 @@
 
 Required properties:
 
-- compatible: should be "brcm,bcm7445-switch-v4.0" or "brcm,bcm7278-switch-v4.0"
+- compatible: should be one of
+	"brcm,bcm7445-switch-v4.0"
+	"brcm,bcm7278-switch-v4.0"
+	"brcm,bcm7278-switch-v4.8"
 - reg: addresses and length of the register sets for the device, must be 6
   pairs of register addresses and lengths
 - interrupts: interrupts for the devices, must be two interrupts

drivers/net/dsa/bcm_sf2.c

@@ -948,6 +948,9 @@ static const struct of_device_id bcm_sf2_of_match[] = {
 	{ .compatible = "brcm,bcm7278-switch-v4.0",
 	  .data = &bcm_sf2_7278_data
 	},
+	{ .compatible = "brcm,bcm7278-switch-v4.8",
+	  .data = &bcm_sf2_7278_data
+	},
 	{ /* sentinel */ },
 };
 MODULE_DEVICE_TABLE(of, bcm_sf2_of_match);