Use `scm_gc_malloc_pointerless' in various places (improves performance).

Use `scm_gc_malloc_pointerless' in various places (improves performance).

* libguile/fports.c (scm_fport_buffer_add): Use
  `scm_gc_malloc_pointerless ()' instead of `scm_gc_malloc ()' when
  allocating room for the read/write buffers.

* libguile/numbers.c (scm_c_make_rectangular): Likewise.

* libguile/ports.c (scm_ungetc): Likewise.

* libguile/random.c (scm_i_copy_rstate): Likewise.
  (scm_c_make_rstate): Likewise.

* libguile/regex-posix.c (scm_make_regexp): Likewise.

git-archimport-id: lcourtes@laas.fr--2005-libre/guile-core--boehm-gc--1.9--patch-36