print-rtl: Change return type of two print functions from int to void

print-rtl: Change return type of two print functions from int to void

Also change one internal variable to bool.

gcc/ChangeLog:

	* rtl.h (print_rtl_single): Change return type from int to void.
	(print_rtl_single_with_indent): Ditto.
	* print-rtl.h (class rtx_writer): Ditto.  Change m_sawclose to bool.
	* print-rtl.cc (rtx_writer::rtx_writer): Update for m_sawclose change.
	(rtx_writer::print_rtx_operand_code_0): Ditto.
	(rtx_writer::print_rtx_operand_codes_E_and_V): Ditto.
	(rtx_writer::print_rtx_operand_code_i): Ditto.
	(rtx_writer::print_rtx_operand_code_u): Ditto.
	(rtx_writer::print_rtx_operand): Ditto.
	(rtx_writer::print_rtx): Ditto.
	(rtx_writer::finish_directive): Ditto.
	(print_rtl_single): Change return type from int to void
	and adjust function body accordingly.
	(rtx_writer::print_rtl_single_with_indent): Ditto.