Use a script specific description in CLI help

Previous changes used the docstring of the test_generation module,
which does not inform a user about the script.

Signed-off-by: Werner Lewis <werner.lewis@arm.com>

scripts/mbedtls_dev/test_generation.py

@@ -179,9 +179,9 @@ class TestGenerator:
         test_cases = self.targets[name](*target_args)
         self.write_test_data_file(name, test_cases)
 
-def main(args, generator_class: Type[TestGenerator] = TestGenerator):
+def main(args, description: str, generator_class: Type[TestGenerator] = TestGenerator):
     """Command line entry point."""
-    parser = argparse.ArgumentParser(description=__doc__)
+    parser = argparse.ArgumentParser(description=description)
     parser.add_argument('--list', action='store_true',
                         help='List available targets and exit')
     parser.add_argument('--list-for-cmake', action='store_true',

tests/scripts/generate_bignum_tests.py

@@ -233,6 +233,6 @@ class BignumAdd(BignumOperation):
     def result(self) -> str:
         return quote_str("{:x}".format(self.int_a + self.int_b))
 
-
 if __name__ == '__main__':
-    test_generation.main(sys.argv[1:])
+    # Use the section of the docstring relevant to the CLI as description
+    test_generation.main(sys.argv[1:], "\n".join(__doc__.splitlines()[:4]))

tests/scripts/generate_psa_tests.py

@@ -917,4 +917,4 @@ class PSATestGenerator(test_generation.TestGenerator):
         super().generate_target(name, self.info)
 
 if __name__ == '__main__':
-    test_generation.main(sys.argv[1:], PSATestGenerator)
+    test_generation.main(sys.argv[1:], __doc__, PSATestGenerator)