Warning fixes -- dbusbind.

Warning fixes -- dbusbind.

This changeset fixes all but 4 or 5 compiler warnings in dbusbind.  The
warnings that are left are some "implicit declaration of function 'foo'"
for some GNU/Emacs functions that I don't yet know what to do with.

	* modules/dbus/dbusbind.c (xd_find_watch_fd): Don't use
	`dbus_watch_get_fd()', it's deprecated.

	* modules/dbus/dbusbind.c (Fdbus_init_bus): Initialise busp to
	NULL.

	* modules/dbus/dbusbind.c (Fdbus_method_return_internal):
	Initialise serial to 0.

	* modules/dbus/dbusbind.c (Fdbus_method_error_internal): Ditto.

	* modules/dbus/dbusbind.c (Fdbus_register_service): If all else
	fails, return Qnil.

	* modules/dbus/dbusbind.h (SBYTES): No need to call XSTRING as
	XSTRING_LENGTH does that for us.

	* modules/dbus/dbusbind.h (XD_ERROR): Correctly cast mess to work
	right for our make_string().

	* modules/dbus/dbusbind.h (syms_of_dbusbind): Add.

Signed-off-by: Steve Youngs <steve@sxemacs.org>