net: dsa: mv88e6xxx: MV88E6097 does not support jumbo configuration

net: dsa: mv88e6xxx: MV88E6097 does not support jumbo configuration

The MV88E6097 chip does not support configuring jumbo frames. Prior to
commit 9dfe41eb6f24 only the 6352, 6351, 6165 and 6320 chips configured
jumbo mode. The refactor accidentally added the function for the 6097.
Remove the erroneous function pointer assignment.

Fixes: 9dfe41eb6f24 ("net: dsa: mv88e6xxx: Refactor setting of jumbo frames")
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>