analyzer: add more feasibility test cases [PR93355,PR96374]

analyzer: add more feasibility test cases [PR93355,PR96374]

This patch adds a couple more reduced test cases derived from the
integration test for PR analyzer/93355.  In both cases, the analyzer
falsely rejects the buggy code paths as being infeasible due to
PR analyzer/96374, and so the tests are marked as XFAIL for now.

gcc/testsuite/ChangeLog:
	PR analyzer/93355
	PR analyzer/96374
	* gcc.dg/analyzer/pr93355-localealias-feasibility-2.c: New test.
	* gcc.dg/analyzer/pr93355-localealias-feasibility-3.c: New test.