c++: ICE with -Wlogical-op [PR107755]

c++: ICE with -Wlogical-op [PR107755]

Here we crash in the middle end because warn_logical_operator calls
build_range_check which calls various fold_* functions and those
don't work too well when we're still processing template trees.  For
instance here we crash because we're converting a RECORD_TYPE to bool.
At this point VIEW_CONVERT_EXPR<struct Foo>(b) hasn't yet been converted
to Foo::operator bool (&b).

I was excited to fix this with instantiation_dependent_expression_p
which can now be called from c-family/ as well, but the problem isn't
that the expression is dependent.  So, p_t_d it is.

	PR c++/107755

gcc/cp/ChangeLog:

	* call.cc (build_new_op): Don't call warn_logical_operator when
	processing a template.

gcc/testsuite/ChangeLog:

	* g++.dg/warn/Wlogical-op-4.C: New test.