net: dsa: mv88e6xxx: Move forward declaration to where it is needed

Move it out from the middle for the #defines to just before it is
needed.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/dsa/mv88e6xxx/mv88e6xxx.h

@@ -662,8 +662,6 @@ enum mv88e6xxx_cap {
 	 MV88E6XXX_FLAGS_PVT |		\
 	 MV88E6XXX_FLAGS_SERDES)
 
-struct mv88e6xxx_ops;
-
 #define MV88E6XXX_FLAGS_FAMILY_6390	\
 	(MV88E6XXX_FLAG_EEE |		\
 	 MV88E6XXX_FLAG_GLOBAL2 |	\
@@ -673,6 +671,8 @@ struct mv88e6xxx_ops;
 	 MV88E6XXX_FLAGS_MULTI_CHIP |	\
 	 MV88E6XXX_FLAGS_PVT)
 
+struct mv88e6xxx_ops;
+
 struct mv88e6xxx_info {
 	enum mv88e6xxx_family family;
 	u16 prod_num;