Use const for name so that static strings can be passed in C++

src/outputlist.c

@@ -208,7 +208,7 @@ void output_list_read_next_time(struct output_list *t, const struct engine *e,
  * time)
  */
 void output_list_init(struct output_list **list, const struct engine *e,
-                      char *name, double *delta_time, double *time_first) {
+                      const char *name, double *delta_time, double *time_first) {
   struct swift_params *params = e->parameter_file;
 
   /* get cosmo */

src/outputlist.h

@@ -56,7 +56,7 @@ void output_list_read_file(struct output_list *outputlist, const char *filename,
 void output_list_read_next_time(struct output_list *t, const struct engine *e,
                                 const char *name, integertime_t *ti_next);
 void output_list_init(struct output_list **list, const struct engine *e,
-                      char *name, double *delta_time, double *time_first);
+                      const char *name, double *delta_time, double *time_first);
 void output_list_print(const struct output_list *outputlist);
 void output_list_clean(struct output_list *outputlist);
 void output_list_struct_dump(struct output_list *list, FILE *stream);