soc: qcom: ipa: filter and routing tables

This patch contains code implementing filter and routing tables for
the IPA.  A filter table allows rules to be used for filtering
packets that depart the AP at an endpoint.  A filter table entry
contains the address of a set of rules to apply for each endpoint
that supports filtering.

A routing table allows packets to be routed to an endpoint based
on packet metadata.  It is also a table whose entries each contain
the address of a set of routing rules to apply.

Neither filtering nor routing is supported by the current driver.
All table entries refer to rules that mean "no filtering" and "no
routing."

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>