bitbake: bin/bitbake: No need to show tracebacks for BBHandledExceptions

For BBHandledExceptions, we've already displaced a sensible error to
the user so we don't need to do it again. Just exit with an error
value.

(Bitbake rev: 1ff5ec26eba70ab1c85674a60b7dac77317bf349)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/bin/bitbake

@@ -323,6 +323,8 @@ def main():
 if __name__ == "__main__":
     try:
         ret = main()
+    except bb.BBHandledException:
+        ret = 1
     except Exception:
         ret = 1
         import traceback