Convert scm_gc_malloc* calls to scm_allocate*

* libguile/arrays.c:
* libguile/bitvectors.c:
* libguile/bytevectors.c:
* libguile/chooks.c:
* libguile/continuations.c:
* libguile/control.c:
* libguile/dynstack.c:
* libguile/ephemerons.c:
* libguile/filesys.c:
* libguile/foreign.c:
* libguile/fports.c:
* libguile/frames.c:
* libguile/gsubr.c:
* libguile/hashtab.c:
* libguile/i18n.c:
* libguile/integers.c:
* libguile/intrinsics.c:
* libguile/load.c:
* libguile/loader.c:
* libguile/macros.c:
* libguile/numbers.c:
* libguile/options.c:
* libguile/ports.c:
* libguile/programs.h:
* libguile/random.c:
* libguile/read.c:
* libguile/regex-posix.c:
* libguile/smob.c:
* libguile/srfi-14.c:
* libguile/strings.c:
* libguile/struct.c:
* libguile/threads.c:
* libguile/threads.h:
* libguile/values.c:
* libguile/vm.c: Convert all calls to scm_gc_malloc_pointerless to
scm_allocate_pointerless.  Convert scm_gc_malloc to either
scm_allocate_tagged or scm_allocate_sloppy, depending on whether the
value can be precisely traced or not.

libguile/struct.c

@@ -141,8 +141,8 @@ set_vtable_access_fields (SCM vtable)
     {
       size_t bitmask_size = (nfields + 31U) / 32U;
       unboxed_fields =
-        scm_gc_malloc_pointerless (bitmask_size * sizeof (*unboxed_fields),
-                                   "unboxed fields");
+        scm_allocate_pointerless (SCM_I_CURRENT_THREAD,
+                                  bitmask_size * sizeof (*unboxed_fields));
       memset (unboxed_fields, 0, bitmask_size * sizeof (*unboxed_fields));
       for (size_t field = 0; field < nfields; field++)
         if (c_layout[field*2] == 'u')