[PR107170] Avoid copying incompatible types in legacy VRP.

[PR107170] Avoid copying incompatible types in legacy VRP.

Legacy VRP is calling ranger deep inside the bowels, and then trying to
copy an incompatible type.  My previous patch in this area assumed that
the only possibility out of vr_values::get_value_range for an
unsupported type was VARYING, but UNDEFINED can also be returned.

	PR tree-optimization/107170

gcc/ChangeLog:

	* vr-values.cc (vr_values::range_of_expr):  Do not die on
	unsupported types.

gcc/testsuite/ChangeLog:

	* gcc.dg/tree-ssa/pr107170.c: New test.