Use debian's name for libsdl2 in the debian package dependency list

platform/unix/debian/control.in

@@ -33,7 +33,7 @@ Depends: ${misc:Depends},
          libgl1-mesa-glx,
          libluajit-5.1-2,
          libphysfs-1.0-0,
-         libsdl2 (>= 2.0.0),
+         libsdl2-2.0-0 (>= 2.0.0),
          libopenal1,
          libogg0,
          libvorbis0a,