Allow injecting user synchronization modules

[mkurc-ant]

This PR allows injection of modules containing synchronization flip-flops (answers #51).

The config script allows to set additional parameters which end up in code as capitalized defines:

tech_specific_rv_sync - enables usage of the user module
user_rv_sync - specifies the module name

The PR is based on #54 and should be reviewed and merged after it.

[varuns-nvidia]

Hi @mkurc-ant , what is the status of this issue?

[mkurc-ant]

Hi @varuns-nvidia. This PR is ready but marked as draft as it is based on #54 (shared codebase) which has not yet been reviewed.

[mkurc-ant]

@varuns-nvidia FYI this is ready for review.

[nstewart-amd]

The user_rv_sync placeholder module should not contain an "initial" block.

The user_rv_sync module should not be multi-bit width, since it has no synchronization qualifiers for multi-bit signal synchronization.

Recommend user_rv_sync is single bit in/out.
Recommend user_rv_sync instantiates rvdff behavioural flop model from existing beh_lib.sv.

[mkurc-ant]

@nstewart-amd I changed the required user synchronizer cell model to be 1-bit and without any initial blocks. I left the behavioral code in design/dmi/dmi_jtag_to_core_sync.v as it was like that before my changes (It would be best to tackle this in a separate PR if needed). I also left the behavioral code in user_rv_sync as it is not used by default. When enabled it is used only in the testbench.