c++: unexpected ADDR_EXPR after overload set pruning [PR107461]

c++: unexpected ADDR_EXPR after overload set pruning [PR107461]

Here the ahead-of-time overload set pruning in finish_call_expr is
unintentionally returning a CALL_EXPR whose (pruned) callee is wrapped
in an ADDR_EXPR, despite the original callee not being wrapped in an
ADDR_EXPR.  This ends up causing a bogus declaration mismatch error in
the below testcase because the call to min in #1 gets expressed as a
CALL_EXPR of ADDR_EXPR of FUNCTION_DECL, whereas the level-lowered call
to min in #2 gets expressed instead as a CALL_EXPR of FUNCTION_DECL.

This patch fixes this by stripping the spurious ADDR_EXPR appropriately.
Thus the first call to min now also gets expressed as a CALL_EXPR of
FUNCTION_DECL, matching the behavior before r12-6075-g2decd2cabe5a4f.

	PR c++/107461

gcc/cp/ChangeLog:

	* semantics.cc (finish_call_expr): Strip ADDR_EXPR from
	the selected callee during overload set pruning.

gcc/testsuite/ChangeLog:

	* g++.dg/template/call9.C: New test.