Enhance OpenACC 'kernels' decomposition testing

Enhance OpenACC 'kernels' decomposition testing

	gcc/testsuite/
	* c-c++-common/goacc/kernels-decompose-1.c: Enhance.
	* c-c++-common/goacc/kernels-decompose-2.c: Likewise.
	* c-c++-common/goacc/kernels-decompose-ice-1.c: Likewise.
	* c-c++-common/goacc/kernels-decompose-ice-2.c: Likewise.
	* gfortran.dg/goacc/kernels-decompose-1.f95: Likewise.
	* gfortran.dg/goacc/kernels-decompose-2.f95: Likewise.
	libgomp/
	* testsuite/libgomp.oacc-c-c++-common/declare-vla-kernels-decompose-ice-1.c:
	Enhance.
	* testsuite/libgomp.oacc-c-c++-common/declare-vla-kernels-decompose.c:
	Likewise.
	* testsuite/libgomp.oacc-c-c++-common/declare-vla.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/f-asyncwait-1.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/f-asyncwait-2.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/f-asyncwait-3.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/kernels-decompose-1.c:
	Likewise.
	* testsuite/libgomp.oacc-fortran/asyncwait-1.f90: Likewise.
	* testsuite/libgomp.oacc-fortran/asyncwait-2.f90: Likewise.
	* testsuite/libgomp.oacc-fortran/asyncwait-3.f90: Likewise.
	* testsuite/libgomp.oacc-fortran/pr94358-1.f90: Likewise.