message: Mention in validation that IsWitnessStandard tests for P2TR
diff: @@ -630,7 +630,7 @@ bool MemPoolAccept::PreChecks(ATMPArgs& args, Workspace& ws)
  return state.Invalid(TxValidationResult::TX_INPUTS_NOT_STANDARD, "bad-txns-nonstandard-inputs");
  }
  - // Check for non-standard witness in P2WSH
  + // Check for non-standard witnesses.
  if (tx.HasWitness() && fRequireStandard && !IsWitnessStandard(tx, m_view))
  return state.Invalid(TxValidationResult::TX_WITNESS_MUTATED, "bad-witness-nonstandard");
  