Update ranger timestamps for inferred ranges.

If an inferred range is added for a name, mark the name as an updated
range to allow the dependency processing to pick up the change.

	PR tree-optimization/126110
	gcc/
	* gimple-range-cache.cc (ranger_cache::mark_stale): Default defs
	get a new timestamp to make them stale.
	* gimple-range-infer.cc (infer_range_manager::add_range): When
	an inferred range is added, mark the name as updated.

	gcc/testsuite/
	* gcc.dg/pr126110.c: New.