Split project Makefrag into multiple components

[nandor]

Project-specific Makefrags are now split into multiple bits. This allows the build flow to first gather all configuration, then define individual rules based on them.

The following makefrags must be present in the folder:

• config.mk: override configuration variables with project specifics
• build.mk: define the build rule generating the input FIRRTL and annotations
• driver.mk: define the configuration for the driver
• run.mk: define rules to run the simulator binaries.

Related PRs / Issues

UI / API Impact

External projects must split Makefrag into multiple bits.

Verilog / AGFI Compatibility

Contributor Checklist

• Is this PR's title suitable for inclusion in the changelog and have you added a changelog:<topic> label?
• Did you add Scaladoc/docstring/doxygen to every public function/method?
• Did you add at least one test demonstrating the PR?
• Did you delete any extraneous prints/debugging code?
• Did you state the UI / API impact?
• Did you specify the Verilog / AGFI compatibility impact?

• If applicable, did you regenerate and publicly share default AGFIs?

• If applicable, did you apply the ci:fpga-deploy label?

• If applicable, did you apply the Please Backport label?

Reviewer Checklist (only modified by reviewer)

Note: to run CI on PRs from forks, comment @Mergifyio copy main and manage the change from the new PR.

• Is the title suitable for inclusion in the changelog and does the PR have a changelog:<topic> label?
• Did you mark the proper release milestone?
• Did you check whether all relevant Contributor checkboxes have been checked?

[davidbiancolin]

Minor name fixes.