move several bitmaps from gc memory to the default obstack and use auto_bitmap

move several bitmaps from gc memory to the default obstack and use auto_bitmap

These places where probably trying to use the default bitmap obstack,
but passing 0 to bitmap_initialize actually uses gc allocation.  In any
case they are all cleaned up before going out of scope so using
auto_bitmap should be fine.

gcc/ChangeLog:

2017-05-13  Trevor Saunders  <tbsaunde+gcc@tbsaunde.org>

	* haifa-sched.c (estimate_shadow_tick): Replace manual bitmap
	management with auto_bitmap.
	(fix_inter_tick): Likewise.
	(fix_recovery_deps): Likewise.
	* ira.c (add_store_equivs): Likewise.
	(find_moveable_pseudos): Likewise.
	(split_live_ranges_for_shrink_wrap): Likewise.
	* print-rtl.c (rtx_reuse_manager::rtx_reuse_manager): Likewise.
	(rtx_reuse_manager::seen_def_p): Likewise.
	(rtx_reuse_manager::set_seen_def): Likewise.
	* print-rtl.h (class rtx_reuse_manager): Likewise.

From-SVN: r248022