message: Return nullptr from GetLegacyScriptPubKeyMan if descriptor wallet
diff: @@ -4324,6 +4324,9 @@ std::unique_ptr<SigningProvider> CWallet::GetSolvingProvider(const CScript& scri
  LegacyScriptPubKeyMan* CWallet::GetLegacyScriptPubKeyMan() const
  {
  + if (IsWalletFlagSet(WALLET_FLAG_DESCRIPTORS)) {
  + return nullptr;
  + }
  // Legacy wallets only have one ScriptPubKeyMan which is a LegacyScriptPubKeyMan.
  // Everything in m_internal_spk_managers and m_external_spk_managers point to the same legacyScriptPubKeyMan.
  auto it = m_internal_spk_managers.find(OutputType::LEGACY);
  @@ -4339,7 +4342,7 @@ LegacyScriptPubKeyMan* CWallet::GetOrCreateLegacyScriptPubKeyMan()
  void CWallet::SetupLegacyScriptPubKeyMan()
  {
  - if (!m_internal_spk_managers.empty() || !m_external_spk_managers.empty() || !m_spk_managers.empty()) {
  + if (!m_internal_spk_managers.empty() || !m_external_spk_managers.empty() || !m_spk_managers.empty() || IsWalletFlagSet(WALLET_FLAG_DESCRIPTORS)) {
  return;
  }
  