postreload.c: Use rtx_insn (also touches rtl.h and cprop.c)

postreload.c: Use rtx_insn (also touches rtl.h and cprop.c)

gcc/
	* rtl.h (fis_get_condition): Strengthen param "jump" from rtx to
	rtx_insn *.

	* cprop.c (fis_get_condition): Likewise.

	* postreload.c (reload_cse_regs): Likewise for param "first".
	(reload_cse_simplify): Likewise for param "insn".
	(reload_cse_regs_1): Likewise for local "insn".
	(reload_cse_simplify_set): Likewise for param "insn".
	(reload_cse_simplify_operands): Likewise.
	(struct reg_use): Likewise for field "insn".
	(reload_combine_purge_insn_uses): Likewise for param "insn".
	(fixup_debug_insns): Likewise for params "from", "to" and local
	"insn".
	(try_replace_in_use): Likewise for local "use_insn".
	(reload_combine_recognize_const_pattern): Likewise for param
	"insn" and locals "add_moved_after_insn", "use_insn".
	(reload_combine_recognize_pattern): Likewise for param "insn" and
	local "prev".
	(reload_combine): Likewise for locals "insn", "prev".
	(reload_combine_note_use): Likewise for param "insn".
	(move2add_use_add2_insn): Likewise.
	(move2add_use_add3_insn): Likewise.
	(reload_cse_move2add): Likewise, also for local "next".
	(move2add_note_store): Likewise for local "insn".

From-SVN: r214358