bitcoin-tx: Fix JSON validation of prevtxs
bitcoin-tx: Fix JSON validation of prevtxs

Github-Pull: #5528
Rebased-From: 2a3d988b802dcea4453241e37168d8511078940a a089c50981e822014ffc18e8a37b3518feb52206 2c14d1532fe66a243cdbfb7de48b298213305765

MazaCoin/maza,MazaCoin/maza,MazaCoin/maza,MazaCoin/maza,MazaCoin/maza,MazaCoin/maza