Removed _inner suffix from

Removed _inner suffix from
GC_make_disappearing_links_disappear_inner and
GC_remove_dangling_disappearing_links_inner.
Also replace 0 with NULL for pointers for refactored codes.
Moved DCL_LOCK_STATE to immediately follow last local var decl.
GC_move_disappearing_link_locked: rename back to
GC_move_disappearing_link_inner.
* finalize.c (GC_make_disappearing_links_disappear,
GC_remove_dangling_disappearing_links,
GC_move_disappearing_link_inner, GC_move_disappearing_link) :
As described above.