net: dsa: bcm_sf2: Move writing of CFP_DATA(5) into slicing functions

In preparation for matching VLANs, move the writing of CFP_DATA(5) into
the IPv4 and IPv6 slicing logic since they are part of the per-flow
configuration.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>