dtoc: Return a non-zero exit code when tests fail

At present 'dtoc -t' return a success code even if some of the tests fail.
Fix this by checking the test result and setting the exit code. This
allows 'make qcheck' to function as expected.
Signed-off-by: NSimon Glass <sjg@chromium.org>

tools/dtoc/dtoc.py

@@ -71,6 +71,10 @@ def run_tests(args):
         print(err)
     for _, err in result.failures:
         print(err)
+    if result.errors or result.failures:
+        print('dtoc tests FAILED')
+        return 1
+    return 0
 
 def RunTestCoverage():
     """Run the tests and check that we get 100% coverage"""
@@ -101,7 +105,8 @@ parser.add_option('-T', '--test-coverage', action='store_true',
 
 # Run our meagre tests
 if options.test:
-    run_tests(args)
+    ret_code = run_tests(args)
+    sys.exit(ret_code)
 
 elif options.test_coverage:
     RunTestCoverage()