calls: Change return type of predicate function from int to bool

calls: Change return type of predicate function from int to bool

Also change some internal variables and some function arguments to bool.

gcc/ChangeLog:

	* calls.h (setjmp_call_p): Change return type from int to bool.
	* calls.cc (struct arg_data): Change "pass_on_stack" to bool.
	(store_one_arg): Change return type from int to bool
	and adjust function body accordingly.  Change "sibcall_failure"
	variable to bool.
	(finalize_must_preallocate): Ditto.  Change *must_preallocate pointer
	argument  to bool.  Change "partial_seen" variable to bool.
	(load_register_parameters):  Change *sibcall_failure
	pointer argument to bool.
	(check_sibcall_argument_overlap_1): Change return type from int to bool
	and adjust function body accordingly.
	(check_sibcall_argument_overlap):  Ditto.  Change
	"mark_stored_args_map" argument to bool.
	(emit_call_1): Change "already_popped" variable to bool.
	(setjmp_call_p): Change return type from int to bool
	and adjust function body accordingly.
	(initialize_argument_information): Change *must_preallocate
	pointer argument to bool.
	(expand_call): Change "pcc_struct_value", "must_preallocate"
	and "sibcall_failure" variables to bool.
	(emit_library_call_value_1): Change "pcc_struct_value"
	variable to bool.