hush: plug the leak on NOMMU re-execute path

function                                             old     new   delta
clean_up_after_re_execute                              -      58     +58
re_execute_shell                                     226     244     +18
run_pipe                                            1271    1276      +5
generate_stream_from_string                          133     138      +5
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(add/remove: 1/0 grow/shrink: 3/0 up/down: 86/0)               Total: 86 bytes

1 file changed