Jim Casey talks with Midland about celebrating their No. 1 debut single, “Drinkin’ Problem,” how Dwight Yoakam contributed to the origin of their band name, the best Dwight Yoakam songs, the importance of a good Al Pacino impression, the joy of making timeless songs with talented songwriters, the Sept. 22 release of their debut album, On the Rocks, and more. Show…