Introduce gen-pass-instances.awk and pass-instances.def

Introduce gen-pass-instances.awk and pass-instances.def

Introduce a new gen-pass-instances.awk script, and use it at build time
to make a pass-instances.def from passes.def.

gcc/

	* Makefile.in (pass-instances.def): New.
	(passes.o): Replace dependency on passes.def with one on
	pass-instances.def

	* gen-pass-instances.awk: New.

	* passes.c (pass_manager::pass_manager): Use pass-instances.def
	rather than passes.def, updating local definition of NEXT_PASS
	macro to add an extra NUM parameter (currently unused).

From-SVN: r201359