Shrink points-to analysis dumps when not dumping with -details

The following allows to get PTA stats with -stats without blowing
up your filesystem by guarding constraint and solution dumping
with TDF_DETAILS and the SSA points-to info with TDF_DETAILS
or TDF_ALIAS.

	* tree-ssa-structalias.cc (dump_sa_stats): Split out from...
	(dump_sa_points_to_info): ... this function.
	(compute_points_to_sets): Guard large dumps with TDF_DETAILS,
	and call dump_sa_stats guarded with TDF_STATS.
	(ipa_pta_execute): Likewise.
	(compute_may_aliases): Guard dump_alias_info with
	TDF_DETAILS|TDF_ALIAS.

	* gcc.dg/ipa/ipa-pta-16.c: Use -details for dump.
	* gcc.dg/tm/alias-1.c: Likewise.
	* gcc.dg/tm/alias-2.c: Likewise.
	* gcc.dg/torture/ipa-pta-1.c: Likewise.
	* gcc.dg/torture/pr39074-2.c: Likewise.
	* gcc.dg/torture/pr39074.c: Likewise.
	* gcc.dg/torture/pta-callused-1.c: Likewise.
	* gcc.dg/torture/pta-escape-1.c: Likewise.
	* gcc.dg/torture/pta-ptrarith-1.c: Likewise.
	* gcc.dg/torture/pta-ptrarith-2.c: Likewise.
	* gcc.dg/torture/pta-ptrarith-3.c: Likewise.
	* gcc.dg/torture/pta-structcopy-1.c: Likewise.
	* gcc.dg/torture/ssa-pta-fn-1.c: Likewise.
	* gcc.dg/tree-ssa/alias-19.c: Likewise.
	* gcc.dg/tree-ssa/pta-callused.c: Likewise.
	* gcc.dg/tree-ssa/pta-fp.c: Likewise.
	* gcc.dg/tree-ssa/pta-ptrarith-1.c: Likewise.
	* gcc.dg/tree-ssa/pta-ptrarith-2.c: Likewise.