blockchain: make some flag twiddling code closer to the original
blockchain: make some flag twiddling code closer to the original

Probably paranoid and unnecessary

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