return preimage in lnpay. fixes #5794
return preimage in lnpay. fixes #5794

pooler/electrum-ltc,wakiyamap/electrum-mona,wakiyamap/electrum-mona,wakiyamap/electrum-mona,pooler/electrum-ltc,vialectrum/vialectrum,vialectrum/vialectrum,vialectrum/vialectrum,pooler/electrum-ltc,pooler/electrum-ltc,spesmilo/electrum,spesmilo/electrum,spesmilo/electrum,spesmilo/electrum,wakiyamap/electrum-mona