(SCM_GC_SET_ALLOCATED, scm_debug_newcell,

(SCM_GC_SET_ALLOCATED, scm_debug_newcell,
scm_debug_newcell2, scm_tc16_allocated): Removed from header.
(scm_deprecated_newcell, scm_deprecated_newcell2): New.
(SCM_NEWCELL, SCM_NEWCELL2): Implement in terms of
scm_deprecated_newcell and scm_deprecated_newcell2.

gc.c (scm_tc16_allocated): Only define when including deprecated
features.
(scm_debug_newcell, scm_debug_newcell2): Removed.
(scm_init_storage): Do not initialize scm_tc16_allocated.
(scm_init_gc): Do it here.
(allocated_mark): New, from old code.
(scm_deprecated_newcell, scm_deprecated_newcell2): New.