Bump to latest rocket-chip | integrated fixed-point | pull in stage/phase

[jerryz123]

This bumps to latest rocket-chip/dsp-tools/rocket-dsp-utils.

• https://github.com/ucb-bar/fixedpoint replaces chisel3.experimental.fixedpoint, thanks @milovanovic and @konda-x1 for all the good work
• stage/phase is pulled into Chipyard, as it has been removed from rocket-chip
• zero-width wires now must be driven
• DontCares have to be explicit for unused, previously unconnected bundle fields

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?

[konda-x1]

Could you bump fixedpoint, dsptools, and rocket-dsp-utils again before merging?

[jerryz123]

Could you bump fixedpoint, dsptools, and rocket-dsp-utils again before merging?

Sure