remove uses of trampolines within guile itself

remove uses of trampolines within guile itself

* libguile/eval.c (scm_map, scm_for_each)
* libguile/hashtab.c (scm_hash_for_each_handle)
* libguile/list.c (scm_filter, scm_filter_x)
* libguile/quicksort.i.c:
* libguile/sort.c (scm_restricted_vector_sort_x, scm_sorted_p)
  (scm_merge, scm_merge_list_x, scm_merge_x)
  (scm_merge_list_step, scm_sort_x, scm_sort, scm_merge_vector_x)
  (scm_merge_vector_step, scm_stable_sort_x, scm_sort_list_x)
  (scm_sort_list)nn
* libguile/srfi-13.c (scm_string_any, scm_string_every)
  (scm_string_tabulate, scm_string_trim, string_trim_right)
  (scm_string_trim_both, scm_string_index, scm_string_index_right)
  (scm_string_skip, scm_string_skip_right, scm_string_count)
  (scm_string_map, scm_string_map_x, scm_string_for_each)
  (scm_string_for_each_index, scm_string_filter, scm_string_delete):
  Remove uses of trampolines.