By Byron Kaye and Shashwat Awasthi SYDNEY (Reuters) – Crown Resorts Ltd backed a $6.3 billion buyout from private equity giant Blackstone Inc on Monday, giving billionaire James Packer an exit route from the Australian casino firm beset by scandals and regulatory setbacks. Packer will cash in his chips a decade and a half after he created Crown to shift away from the Packer family’s media empire in a bid to reinvent the dynasty as a gambling business. The A$13.10 cash offer values Crown below its share price in 2019, before COVID-19 restrictions and damaging regulatory inquiries in the three s…