modulo-sched.c: Use rtx_insn in various places

modulo-sched.c: Use rtx_insn in various places

gcc/
	* modulo-sched.c (struct ps_reg_move_info): Strengthen field
	"insn" from rtx to rtx_insn *.
	(ps_rtl_insn): Likewise for return type.
	(doloop_register_get): Likewise for params "head", "tail" and
	locals "insn", "first_insn_not_to_check".
	(schedule_reg_move): Likewise for local "this_insn".
	(schedule_reg_moves): Add a checked cast to rtx_insn * to result
	of gen_move_insn for now.
	(reset_sched_times): Strengthen local "insn" from rtx to
	rtx_insn *.
	(permute_partial_schedule): Likewise.
	(duplicate_insns_of_cycles): Likewise for local "u_insn".
	(dump_insn_location): Likewise for param "insn".
	(loop_canon_p): Likewise for local "insn".
	(sms_schedule): Likewise.
	(print_partial_schedule): Likewise.
	(ps_has_conflicts): Likewise.

From-SVN: r214354