axi_demux: Improve compatibility with VCS

Fixes #187.

Fixes #175.

Fix latch inference on the data width converters with the Mentor Precision synthesis tool

Some tools still require all parameters to have a default value.

axi_lite_cdc_src_intf: Fix `_i` and `_o` suffixes in instantiation of `axi_cdc_src`

Bender v0.18.0 no longer builds due to unmet dependencies.

tb_axi_serializer: Fix channel widths in checker

axi_lite_to_apb_intf: Add missing parameters

axi_xbar and axi_demux: Add support for unique IDs

This configuration is tested in addition to the configuration without
unqiue IDs.  To keep the overall TB runtime comparable even though we
have doubled the number of tested configurations, the number of
transactions per master module is halved.

Also halve the number of transactions per master module to keep the
overall TB runtime comparable even though we have doubled the number of
tested configurations.

Also halve the number of transactions per master module to keep the
overall TB runtime comparable even though we have doubled the number of
tested configurations.

axi_rand_master: Refactor ID legalization

axi_demux: Introduce workaround for bug in new vopt