Revert "Export the FSTAR_HOME defined and used when building the binary package"
Revert "Export the FSTAR_HOME defined and used when building the binary package"

This reverts commit 7161d1f6c1e8bf56386a0020232c604d90eb78e3.

FStarLang/FStar,A-Manning/FStar,A-Manning/FStar,FStarLang/FStar,FStarLang/FStar,A-Manning/FStar