desugar: Drop stale Note [Matching seqId]
desugar: Drop stale Note [Matching seqId]

The need for this note vanished in
eae703aa60f41fd232be5478e196b661839ec3de.

sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc