Convert edge_def.insns.r to rtx_insn *

Convert edge_def.insns.r to rtx_insn *

gcc/
	* basic-block.h (struct edge_def). Strengthen "r" within
	union edge_def_insns from rtx to rtx_insn *.

	* cfgexpand.c (pass_expand::execute): Remove now-redundant cast
	from rtx to rtx_insn *.  Strengthen local "insns" from rtx to
	rtx_insn *.
	* cfgrtl.c (commit_one_edge_insertion): Remove now-redundant cast
	from rtx to rtx_insn *.
	* cprop.c (find_bypass_set): Strengthen local "insn" from rtx to
	rtx_insn *.
	* postreload-gcse.c (reg_killed_on_edge): Likewise.
	(reg_used_on_edge): Likewise.
	* tree-cfg.c (gt_ggc_mx): New overload for rtx_insn *&.
	(gt_pch_nx): New overload for rtx_insn *&.
	* tree-outof-ssa.c (expand_phi_nodes): Strengthen local "insns"
	from rtx to rtx_insn *.

From-SVN: r214471