Add more instance count-related metrics

[donn]

Steps

• OpenROAD.*

  • All steps that modify views now update design area metrics.
  • New metrics added as modifiers of design__instance__count__stdcell
    • type:physical: class:{welltap,antennacell,spacer,misc}
    • type:logical: class:{sequential,buffer,clock_gate,misc}

• Created Odb.CellFrequencyTables

  • Creates a number of tables to show the cell frequencies by:
    • Cells
    • Buffer cells only
    • Cell Function
    • SCL

Tool Updates

• OpenROAD -> bbe940134bddf836894bfd1fe02153f4a38f8ae5
• OpenSTA -> 20925bb00965c1199c45aca0318c2baeb4042c5a

Misc Bugfixes/Enhancements

• openlane.common.metrics
  • aggregate_metrics(): Added support for aggregation of N-modifier levels

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Resolves #254

[openlane-bot]

Failed to create report:

Metrics not found for commit: f18bb22e894bbd9fc5868211602cb049bc447efe.