KVM: selftests: Fix kvm_check_cap() assertion

KVM_CHECK_EXTENSION ioctl can return any negative value on error,
and not necessarily -1. Change the assertion to reflect that.
Signed-off-by: Fuad Tabba <tabba@google.com>
Message-Id: <20210615150443.1183365-1-tabba@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tools/testing/selftests/kvm/lib/kvm_util.c

@@ -82,7 +82,7 @@ int kvm_check_cap(long cap)
 
 	kvm_fd = open_kvm_dev_path_or_exit();
 	ret = ioctl(kvm_fd, KVM_CHECK_EXTENSION, cap);
-	TEST_ASSERT(ret != -1, "KVM_CHECK_EXTENSION IOCTL failed,\n"
+	TEST_ASSERT(ret >= 0, "KVM_CHECK_EXTENSION IOCTL failed,\n"
 		"  rc: %i errno: %i", ret, errno);
 
 	close(kvm_fd);