net: mscc: ocelot: delete OCELOT_MRP_CPUQ

MRP frames are configured to be trapped to the CPU queue 7, and this
number is reflected in the extraction header. However, the information
isn't used anywhere, so just leave MRP frames to go to CPU queue 0
unless needed otherwise.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>