test: compression: Convert to unit test framework

Adjust this test to use the unit test framework. Drop the two existing
commands for running the tests and replace them with a single
'ut compression' command, with sub-commands.

Signed-off-by: Simon Glass <sjg@chromium.org>
[trini: Continue to have ret = run_test_internal(...) in run_test so ret
is always initialized]
Signed-off-by: Tom Rini <trini@konsulko.com>

include/test/compression.h

@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2017 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#ifndef __TEST_COMPRESSION_H__
+#define __TEST_COMPRESSION_H__
+
+#include <test/test.h>
+
+/* Declare a new compression test */
+#define COMPRESSION_TEST(_name, _flags) \
+		UNIT_TEST(_name, _flags, compression_test)
+
+#endif /* __TEST_ENV_H__ */