net: dsa: mv88e6xxx: prefix Port Default VLAN macros

For implicit namespacing and clarity, prefix the common Port Default
VLAN Register macros with MV88E6XXX_PORT_DEFAULT_VLAN.

Document the register and prefer ordered hex masks values for all
Marvell 16-bit registers.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/dsa/mv88e6xxx/port.h b/drivers/net/dsa/mv88e6xxx/port.h
index 23d94f6..44ac132 100644
--- a/drivers/net/dsa/mv88e6xxx/port.h
+++ b/drivers/net/dsa/mv88e6xxx/port.h
@@ -150,8 +150,10 @@
 #define MV88E6XXX_PORT_BASE_VLAN		0x06
 #define MV88E6XXX_PORT_BASE_VLAN_FID_3_0_MASK	0xf000
 
-#define PORT_DEFAULT_VLAN	0x07
-#define PORT_DEFAULT_VLAN_MASK	0xfff
+/* Offset 0x07: Default Port VLAN ID & Priority */
+#define MV88E6XXX_PORT_DEFAULT_VLAN		0x07
+#define MV88E6XXX_PORT_DEFAULT_VLAN_MASK	0x0fff
+
 #define PORT_CONTROL_2		0x08
 #define PORT_CONTROL_2_IGNORE_FCS	BIT(15)
 #define PORT_CONTROL_2_VTU_PRI_OVERRIDE	BIT(14)