When mirroring rules are added in shared filter blocks, the same
mirroring rule has to be configured on all the switch ports that are
part of the same block.

In case a switch port joins a shared block after mirroring filters have
been already added to it, then all the mirror rules should be offloaded
to the port. The reverse, removal of mirroring rules, has to be done at
block unbind.

For this purpose, the dpaa2_switch_block_offload_mirror() and
dpaa2_switch_block_unoffload_mirror() functions are added and called
upon binding and unbinding a switch port to/from a block.
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>