Strenghten bound for bulitin_constant_p hint.

Strenghten bound for bulitin_constant_p hint.

this patch makes builtin_constant_p hint to combine with other loop hints
we already support.

gcc/ChangeLog:

2020-10-22  Jan Hubicka  <hubicka@ucw.cz>

	PR ipa/97445
	* ipa-inline.c (inline_insns_single): Add hint2 parameter.
	(inline_insns_auto): Add hint2 parameter.
	(can_inline_edge_by_limits_p): Update.
	(want_inline_small_function_p): Update.
	(wrapper_heuristics_may_apply): Update.