Minor cleanups for async DNS etc.

Minor cleanups for async DNS etc.

* src/frame.h (FRAME_WINDOW_CONFIGURATION_CHANGED):
Omit unnecessary parens.
* src/gnutls.c (gnutls_try_handshake, emacs_gnutls_deinit)
(gnutls_verify_boot):
Use bool for boolean.
(ATTRIBUTE_FORMAT_PRINTF): Add printf attribute.
* src/process.c (free_dns_request, Fmake_network_process):
Allocate and free async request control block all in one go.
(set_network_socket_coding_system, finish_after_tls_connection)
(connect_network_socket):
Now static.
(conv_numerical_to_lisp): 2nd arg is now int, not unsigned.
(Fmake_network_process): Use list1 for brevity.
(wait_for_socket_fds): 2nd arg is now const ptr.
* src/process.h (struct Lisp_Process.dns_request):
Now struct gaicb *, not struct gaicb **, since there was always
exactly one.  All uses changed.
* src/window.c, src/window.h (run_window_configuration_change_hook):
Now static.