(DOHASH): Change calling convention

(DOHASH): Change calling convention

This leads to simpler code in the users, and more efficient machine
code because we don't repeatedly need to fetch the `table_size`
and `key_and_value` fields of the hash table object.

* src/lisp.h (DOHASH): Rewrite.
* src/composite.c (composition_gstring_lookup_cache): Simplify.
(composition_gstring_cache_clear_font):
* src/print.c (print):
* src/pdumper.c (hash_table_contents):
* src/minibuf.c (Ftest_completion):
* src/json.c (lisp_to_json_nonscalar_1):
* src/emacs-module.c (module_global_reference_p):
* src/comp.c (compile_function, Fcomp__compile_ctxt_to_file):
* src/fns.c (Fmaphash): Adjust to new calling convention.