A team of attorneys from Kirkland & Ellis LLP scored a victory before an immigration judge in Texas — and they say it may be a first among immigration cases brought during President Donald Trump’s administration.The lawyers represented a Guatemalan immigrant separated from his 6-year-old son by authorities at the Mexican border in May. Last month, he was granted protection under an international anti-torture treaty.Since December, the Kirkland lawyers from Chicago and other offices have represented the man, identified …