Don't try and set SANITIZE in makefile.boot
Don't try and set SANITIZE in makefile.boot

There is no sanitize in the build config.  A too-tolerant SET was
covering up the failed attempt to set the variable.

draegtun/ren-c,rgchris/ren-c,hostilefork/rebol,draegtun/ren-c,giuliolunati/ren-c,hostilefork/rebol,giuliolunati/ren-c,kealist/ren-c,hostilefork/rebol,draegtun/ren-c,rgchris/ren-c,kealist/ren-c,kealist/ren-c,rgchris/ren-c,codebybrett/ren-c,rgchris/ren-c,kealist/ren-c,giuliolunati/ren-c,hostilefork/rebol,hostilefork/rebol,giuliolunati/ren-c,kealist/ren-c,codebybrett/ren-c,draegtun/ren-c,codebybrett/ren-c,giuliolunati/ren-c,rgchris/ren-c,hostilefork/rebol,codebybrett/ren-c,codebybrett/ren-c,codebybrett/ren-c,draegtun/ren-c,kealist/ren-c,draegtun/ren-c