c++: low -faligned-new [PR102071]

c++: low -faligned-new [PR102071]

This test ICEd after the constexpr new patch (r10-3661) because alloc_call
had a NOP_EXPR around it; fixed by moving the NOP_EXPR to alloc_expr.  And
the PR pointed out that the size_t cookie might need more alignment, so I
fix that as well.

	PR c++/102071

gcc/cp/ChangeLog:

	* init.cc (build_new_1): Include cookie in alignment.  Omit
	constexpr wrapper from alloc_call.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp1z/aligned-new9.C: New test.