win32*.sh: cleanup Windows build script

win32*.sh: cleanup Windows build script

Since the switch to Python 3, a few Cmake flags are no longer required.
While at it, we're dropping a few other unused Cmake flags.

We're going to pass the right target os flag when building lz4
and make sure that it's included in our zip archive.

win32_deps_build.sh needs a small change, fixing a sed command to become
idempotent.

Signed-off-by: Lucian Petrut <lpetrut@cloudbasesolutions.com>
Signed-off-by: Mike Latimer <mlatimer@suse.com>