kas-main: do not use return type of void function

The 'kas' function does not return any value, hence we must not use the
return value.

Signed-off-by: Felix Moessbauer <felix.moessbauer@siemens.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>

kas/kas.py

@@ -172,7 +172,7 @@ def main():
     """
 
     try:
-        sys.exit(kas(sys.argv[1:]))
+        kas(sys.argv[1:])
     except Exception as err:
         logging.error('%s', err)
         traceback.print_exc()