External inputs are currently only supported for initial transaction creation functions. Extend `solving_data` arguments as necessary to support fee bumping wallet transactions with non-wallet inputs.

https://github.com/bitcoin/bitcoin/pull/17211#issuecomment-897653994
{
    LOCK(wallet.cs_wallet);
    const CWalletTx* wtx = wallet.GetWalletTx(txid);
    if (wtx == nullptr) return false;
    std::vector<bilingual_str> errors_dummy;
    feebumper::Result res = PreconditionChecks(wallet, *wtx, errors_dummy);
    return res == feebumper::Result::OK;
}
Result CreateRateBumpTransaction(CWallet& wallet, const uint256& txid, const CCoinControl& coin_control, std::vector<bilingual_str>& errors,
                                 CAmount& old_fee, CAmount& new_fee, CMutableTransaction& mtx)
{
    
    CCoinControl new_coin_control(coin_control);
    LOCK(wallet.cs_wallet);
    errors.clear();
    auto it = wallet.mapWallet.find(txid);
    if (it == wallet.mapWallet.end()) {
        errors.push_back(Untranslated("Invalid or non-wallet transaction id"));
        return Result::INVALID_ADDRESS_OR_KEY;
    }
    const CWalletTx& wtx = it->second;
    Result result = PreconditionChecks(wallet, wtx, errors);
    if (result != Result::OK) {