* buffer.c, buffer.h: Use bool for boolean.

* buffer.c, buffer.h: Use bool for boolean.

* buffer.c (reset_buffer_local_variables)
(buffer_lisp_local_variables, Fset_buffer_modified_p)
(Frestore_buffer_modified_p, Fset_buffer_multibyte):
(overlays_at, overlays_in, mouse_face_overlay_overlaps)
(overlay_touches_p, overlay_strings, Foverlay_put)
(report_overlay_modification, call_overlay_mod_hooks):
(mmap_enlarge, mmap_set_vars):
* buffer.h (buffer_has_overlays, uppercasep, lowercasep):
Use bool for booleans, instead of int.
* buffer.c (compact_buffer, mmap_free_1): Return void, not int,
since the 1-or-0 return value is always ignored anyway.
(mmap_initialized_p):
* buffer.h (struct buffer_text.inhibit_shrinking): Now bool, not int.
* buffer.h, lisp.h: Adjust prototypes to match above changes.