Add missing check for const_pool in the escaped solutions

Add missing check for const_pool in the escaped solutions

The ptr-vs-ptr compare folding using points-to info was missing a
check for const_pool being included in the escaped solution.  The
following fixes that, fixing the observed execute FAIL of
experimental/functional/searchers.cc

	* tree-ssa-alias.h (pt_solution_includes_const_pool): Declare.
	* tree-ssa-alias.cc (ptrs_compare_unequal): Use
	pt_solution_includes_const_pool.
	* tree-ssa-structalias.cc (pt_solution_includes_const_pool): New.

	* gcc.dg/torture/20240517-1.c: New testcase.