Fix unwind passing of REDUCE
Fix unwind passing of REDUCE

This fixes CureCode issue #1760: "Unwind functions don't propagate from
REDUCE".

hostilefork/rebol,rebol/rebol,earl/r3,kealist/ren-c,draegtun/ren-c,kealist/ren-c,kealist/ren-c,mbk/ren-c,hostilefork/rebol,rebol/rebol,codebybrett/ren-c,draegtun/ren-c,rebolsource/r3,earl/r3,giuliolunati/ren-c,rgchris/ren-c,rebolsource/r3,rebol/rebol,kealist/ren-c,codebybrett/ren-c,mbk/ren-c,kealist/ren-c,draegtun/ren-c,draegtun/ren-c,mbk/ren-c,hostilefork/rebol,hostilefork/rebol,codebybrett/ren-c,draegtun/ren-c,hostilefork/rebol,codebybrett/ren-c,giuliolunati/ren-c,rebolsource/r3,earl/r3,earl/r3,giuliolunati/ren-c,codebybrett/ren-c,rgchris/ren-c,giuliolunati/ren-c,codebybrett/ren-c,rgchris/ren-c,hostilefork/rebol,rebol/rebol,rgchris/ren-c,giuliolunati/ren-c,kealist/ren-c,rgchris/ren-c,draegtun/ren-c,mbk/ren-c