Fixed --enable-luajit option

configure.in

@@ -18,9 +18,7 @@ AC_ARG_ENABLE([luajit],
 	AC_SEARCH_LIBS(
 		[lua_pcall],
 		[luajit luajit-5.1],
-		if test "$ac_cv_search_lua_pcall" = "-lluajit5.1"; then
-			AC_SUBST([INCLUDE_LUA], [-I/usr/include/luajit-2.0])
-		fi,
+		AC_SUBST([INCLUDE_LUA], [-I/usr/include/luajit-2.0]),
 		AC_MSG_ERROR([Can't LÖVE without LuaJIT])
 	),
 	AC_SEARCH_LIBS(