testsuite: Add -fchecking to dg-ice tests

testsuite: Add -fchecking to dg-ice tests

In --enable-checking=release builds (which is the default on release
branches), I'm getting various extra FAILs that don't appear in
--enable-checking=yes builds.

XPASS: g++.dg/cpp0x/constexpr-52830.C  -std=c++14 (internal compiler error)
FAIL: g++.dg/cpp0x/constexpr-52830.C  -std=c++14 (test for excess errors)
XPASS: g++.dg/cpp0x/constexpr-52830.C  -std=c++17 (internal compiler error)
FAIL: g++.dg/cpp0x/constexpr-52830.C  -std=c++17 (test for excess errors)
XPASS: g++.dg/cpp0x/constexpr-52830.C  -std=c++2a (internal compiler error)
FAIL: g++.dg/cpp0x/constexpr-52830.C  -std=c++2a (test for excess errors)
FAIL: g++.dg/cpp0x/vt-88982.C  -std=c++14 (test for excess errors)
FAIL: g++.dg/cpp0x/vt-88982.C  -std=c++17 (test for excess errors)
FAIL: g++.dg/cpp0x/vt-88982.C  -std=c++2a (test for excess errors)
FAIL: g++.dg/cpp1y/auto-fn61.C  -std=c++14 (test for excess errors)
FAIL: g++.dg/cpp1y/auto-fn61.C  -std=c++17 (test for excess errors)
FAIL: g++.dg/cpp1y/auto-fn61.C  -std=c++2a (test for excess errors)
FAIL: g++.dg/cpp1z/constexpr-lambda26.C  -std=c++17 (test for excess errors)
FAIL: g++.dg/cpp1z/constexpr-lambda26.C  -std=c++2a (test for excess errors)
FAIL: g++.dg/cpp2a/nontype-class39.C  -std=c++2a (test for excess errors)
FAIL: c-c++-common/goacc/kernels-decompose-ice-1.c  -std=c++14 (test for excess errors)
FAIL: c-c++-common/goacc/kernels-decompose-ice-1.c  -std=c++17 (test for excess errors)
FAIL: c-c++-common/goacc/kernels-decompose-ice-1.c  -std=c++2a (test for excess errors)
FAIL: c-c++-common/goacc/kernels-decompose-ice-1.c  -std=c++98 (test for excess errors)
FAIL: c-c++-common/goacc/kernels-decompose-ice-2.c  -std=c++14 (test for excess errors)
FAIL: c-c++-common/goacc/kernels-decompose-ice-2.c  -std=c++17 (test for excess errors)
FAIL: c-c++-common/goacc/kernels-decompose-ice-2.c  -std=c++2a (test for excess errors)
FAIL: c-c++-common/goacc/kernels-decompose-ice-2.c  -std=c++98 (test for excess errors)

These are tests that have dg-ice and most of those ICEs are checking ICEs
which go away in release checking when -fno-checking is the default.

The following patch adds -fchecking option to those.

2021-04-21  Jakub Jelinek  <jakub@redhat.com>

	* g++.dg/cpp1z/constexpr-lambda26.C: Add dg-additional-options
	-fchecking.
	* g++.dg/cpp1y/auto-fn61.C: Likewise.
	* g++.dg/cpp2a/nontype-class39.C: Likewise.
	* g++.dg/cpp0x/constexpr-52830.C: Likewise.
	* g++.dg/cpp0x/vt-88982.C: Likewise.
	* c-c++-common/goacc/kernels-decompose-ice-1.c: Add -fchecking to
	dg-additional-options.
	* c-c++-common/goacc/kernels-decompose-ice-2.c: Likewise.