VLSI Fixes

[nayiri-k]

The clock name for TinyRocketConfig has changed from clock_clock to clock_uncore_clock.
Also the Make variable PREPROC_DEFINES was renamed to SIM_PREPROC_DEFINES, so Hammer was breaking because the sim.defines YAML key was being set to nothing.

Pulling these changes from #1514 so it's easier to merge for the release.

Related PRs / Issues:

Type of change:

• Bug fix
• New feature
• Other enhancement

Impact:

• RTL change
• Software change (RISC-V software)
• Build system change
• Other

Contributor Checklist:

• Did you set main as the base branch?
• Is this PR's title suitable for inclusion in the changelog and have you added a changelog:<topic> label?
• Did you state the type-of-change/impact?
• Did you delete any extraneous prints/debugging code?
• Did you mark the PR with a changelog: label?
• (If applicable) Did you update the conda .conda-lock.yml file if you updated the conda requirements file?
• (If applicable) Did you add documentation for the feature?
• (If applicable) Did you add a test demonstrating the PR?

• (If applicable) Did you mark the PR as Please Backport?