blockchain: fix wallet syncing from scratch
blockchain: fix wallet syncing from scratch

When the wallet syncs from the first block, it is fine to start
at the genesis block.

eiabea/bitmonero,eiabea/bitmonero,eiabea/bitmonero,ranok/bitmonero,ranok/bitmonero,ranok/bitmonero,eiabea/bitmonero,ranok/bitmonero,eiabea/bitmonero,eiabea/bitmonero,ranok/bitmonero,ranok/bitmonero