* insdel.c: Make symbols static if they're not exported.

* insdel.c: Make symbols static if they're not exported.

However, leave prepare_to_modify_buffer alone.  It's never
called from outside this function, but that appears to be a bug.
(combine_after_change_list, combine_after_change_buffer):
(adjust_after_replace): Now static.
(adjust_after_replace_noundo): Remove; unused.
* lisp.h (adjust_after_replace, adjust_after_replace_noundo):
Remove decls.