PR analyzer/93959 reported that g++.dg/analyzer/malloc.C was failing
with no output on Solaris.

The issue is that <stdlib.h> there has "using std::free;", converting
all the "free" calls to std::free, which fails the name-matching via
is_named_call_p.

This patch implements an is_std_named_call_p variant of is_named_call_p
to check for the name within "std", and uses it in sm-malloc.c to check
for std::malloc, std::calloc, and std::free.

gcc/analyzer/ChangeLog:
	PR analyzer/93959
	* analyzer.cc (is_std_function_p): New function.
	(is_std_named_call_p): New functions.
	* analyzer.h (is_std_named_call_p): New decl.
	* sm-malloc.cc (malloc_state_machine::on_stmt): Check for "std::"
	variants when checking for malloc, calloc and free.

gcc/testsuite/ChangeLog:
	PR analyzer/93959
	* g++.dg/analyzer/cstdlib-2.C: New test.
	* g++.dg/analyzer/cstdlib.C: New test.