hush: fix trap clearing in subshells on MMU; simplify NOMMU a bit:

function                                             old     new   delta
parse_stream_dquoted                                 335     324     -11
handle_dollar                                        849     800     -49
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(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-60)             Total: -60 bytes

1 file changed