selftests: kvm: Introduce the TEST_FAIL macro

Some tests/utilities use the TEST_ASSERT(false, ...) pattern to
indicate a failure and stop execution.

This change introduces the TEST_FAIL macro which is a wrap around
TEST_ASSERT(false, ...) and so provides a direct alternative for
failing a test.
Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tools/testing/selftests/kvm/include/test_util.h

@@ -55,6 +55,9 @@ void test_assert(bool exp, const char *exp_str,
 		    #a, #b, #a, (unsigned long) __a, #b, (unsigned long) __b); \
 } while (0)
 
+#define TEST_FAIL(fmt, ...) \
+	TEST_ASSERT(false, fmt, ##__VA_ARGS__)
+
 size_t parse_size(const char *size);
 
 int64_t timespec_to_ns(struct timespec ts);