Bitcoin advocate Michael Saylor is stepping down as the CEO of the software company he co-founded, MicroStrategy, and will instead take on the role of executive chairman. Saylor’s belief in Bitcoin has turned the company into a holding vehicle for the cryptocurrency. The news came as the company reported its second-quarter earnings. It noted a loss of $1.062 billion, mostly due to an impairment charge of $917 million based on the value of its Bitcoin holdings, which have plunged since…