storage: fix bug in convert_version_17
storage: fix bug in convert_version_17

closes #5400

spesmilo/electrum,pooler/electrum-ltc,vialectrum/vialectrum,vialectrum/vialectrum,pooler/electrum-ltc,spesmilo/electrum,fujicoin/electrum-fjc,neocogent/electrum,spesmilo/electrum,wakiyamap/electrum-mona,neocogent/electrum,vialectrum/vialectrum,wakiyamap/electrum-mona,spesmilo/electrum,pooler/electrum-ltc,wakiyamap/electrum-mona,pooler/electrum-ltc,neocogent/electrum,fujicoin/electrum-fjc,fujicoin/electrum-fjc,wakiyamap/electrum-mona