Mariners’ Brendan Donovan set to return to lineup Friday The Mariners, finally, are starting to get some encouraging injury news. Brendan Donovan, the Mariners’ third baseman and leadoff hitter, is traveling to Chicago on Thursday to meet the team and is expected to be activated off the injured list ahead of Friday’s series opener against the White Sox. All-Star catcher Cal Raleigh, meanwhile, is expected to return as the starting catcher on Friday as he continues to manage what he’s described as a sore right side. Raleigh missed three games earlier this week, then returned to the lineup against Atlanta on Tuesday and Wednesday as the designated hitter. He went 0 for 8 with five strikeouts in those two games. Donovan was the Mariners’ most productive hitter in the first three weeks of the season, before landing on the IL on April 20 (retroactive to April 18) because of a left groin strain.…