Real Club Deportivo de La Coruña ( lit. ' Royal Sporting Club of La Coruña ' ), commonly known as Deportivo La Coruña ( pronounced [depoɾˈtiβo la koˈɾuɲa] ) or simply Depor , is a Spanish professional football club based in the city of A Coruña , Galicia, that competes in La Liga , the top tier of Spanish football league system .