Remove controller.c from gitignore

controller.c is not cython generated file (?) so it shouldn't be ignored by git

Author: MightyJosip

.gitignore

@@ -52,4 +52,5 @@ buildconfig/win_dll_dirs.json
 # cython generated files
 src_c/_sdl2/*.c
 !/src_c/_sdl2/touch.c
+!/src_c/_sdl2/controller.c
 src_c/pypm.c